Logical Flaw Questions for CLAT: Describe, Then Match

📑 On this page

⚡ The 20-second answer

A flaw question asks what is wrong with the reasoning, not whether the conclusion is true. Method: split evidence from conclusion, describe the gap in your own words, then match the option that says the same. The #1 trap: an option naming a real fallacy, or describing the argument accurately, that isn't this argument's mistake.

🎬 The 30-second story

The lo-fi reel

“Switched to lo-fi beats. Mock score up 22 marks. Lo-fi = rank booster.”

🎧

Aarav

Aarav's reel crosses 40k views.

“Bro scored 112. If a topper says it, it works.”

💬

Rohan

Rohan, top comment.

“One mock, one change. Was that mock easier? Did you also revise more that week?”

🖊️

Zoya

Zoya describes the gap before naming anything.

“The options had 'attacks the person' and 'ignores other causes'. I picked the fancy one.”

📝

Meher

Meher, in a sectional the next morning.

Tara's verdict: Zoya never used a fallacy name. She described the gap: one before-and-after result, with other explanations ignored. Write that sentence first and the right option, "ignores other causes", picks itself. Describe first, match second.

How does CLAT word flaw questions?

Stem	What it really asks
"Which of the following statements by the author lack credible evidence in the passage?" (2025 Q107)	Which claim is asserted with nothing behind it?
"The argument is flawed because it…" / "most vulnerable to the criticism that it…"	Describe what the author did wrong.
"Which of the following, if true, most weakens…"	A new fact that exploits the same gap.
"The author assumes that…"	The bridge the flaw leaves unbuilt.

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📌 What CLAT actually expects

Honestly: no CLAT Logical Reasoning stem from 2020 to 2025 uses the word "flaw"; 2025 Q107 is the closest. But describing the gap answers weaken, assumption and evidence questions every year. No fallacy names needed.

What is a flaw in an argument?

A flaw is the distance between what the evidence shows and what the conclusion claims. The premises can all be true and the conclusion can even be true; the flaw is that one doesn't earn the other.

🗺️ Argument map

Aarav's reel, mapped

Evidence

Aarav's mock score rose 22 marks in the week he switched to lo-fi.

↓

🌉 Hidden assumption (the bridge)

Nothing else changed that week that could explain the jump.

↓

🎯 Conclusion

Lo-fi music raises mock scores.

What each new fact does

−
That week's mock was rated the easiest of the series.
Weakens · hits the gap — A weakener: a new fact through the gap.
＋
His score rose in four later mocks with lo-fi and fell in two without it.
Strengthens · hits the gap — A strengthener: rules out a one-off.
∅
Lo-fi channels have millions of subscribers.
No effect · hits the conclusion — Popularity says nothing about scores.

Flaw description: "treats one before-and-after result as proof of cause, ignoring other explanations".

Flaw vs weaken: what is the difference?

⚔️ Side by side

Same gap, two stems

🔍Flaw

describes the reasoning

•No new facts
•True of the argument as written

🔨Weaken

adds a fact

•Accept it as true
•Makes the conclusion less likely

Test	Flaw	Weaken
Option starts with	"It assumes…", "It fails to consider…", "It treats…"	A fact about the world
Lo-fi example	"It treats a single improvement as proof of cause."	"That week's mock was the easiest."

A flaw option is about the argument. A weaken option is about the world.

🧭 Decision flow

Which family is this stem?

❓ Does the stem say "if true"?

Yes →

Weaken or strengthen: pick a new fact.

No ↓

❓ Does it ask about the reasoning: flawed, vulnerable, criticism, lacks evidence?

Yes →

Flaw: describe the gap, match the description.

No →

Another family: assumption, inference or main point.

How do you solve a flaw question? Describe, then match

1
Split
One line for the conclusion, one for the evidence. Signal words: so, therefore, clearly, hence.
2
Describe
Before the options, finish: "The author goes from ___ to ___, but ___." Five plain words beat a Latin label.
3
Match
Translate each option into plain English. Keep the one that says your sentence.
4
Confirm
Two checks: did the author really do this? Is it a mistake, so that fixing it would repair the argument?

💡 Read the options last

Options are built to make every gap sound plausible. If you meet them before you have your own sentence, you'll adopt theirs.

How do flaw options describe the common gaps?

Step 3 is translation. CLAT-style options use stiff phrases; each one hides a plain idea you already know.

Your plain description	How the option says it
A few cases stand in for everyone	"generalises from a sample that may not be representative"
Came together or after, so it must be the cause	"overlooks the possibility that another factor…"
Needed, so treated as enough	"treats a condition required for X as sufficient for X"
A key word changes meaning	"uses a term in two different senses"
Just asserted, nothing behind it	"offers no evidence for the claim that…"
Talks about the person or crowd, not the claim	"attacks the source rather than the argument"

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🔬 Option autopsy

Option autopsy: the quiet floor

Students who use the library's quiet floor score higher than those who don't. So every student should spend two hours a day there, and everyone's grades will rise. The reasoning is most vulnerable to the criticism that it…

A overlooks the possibility that students who already study hard are the ones who choose the quiet floor Tag it

✅ Correct

The gap: hard workers may choose the floor, not the other way round.

B relies on the opinion of a single librarian Tag it

❓ Not supported by the text

A real flaw type, absent here.

C some students find the quiet floor too cold Tag it

🛸 Out of scope

A fact about the world, not the reasoning.

D compares students who use the quiet floor with those who don't Tag it

🔁 Just repeats the passage

True, but comparing groups is no mistake.

✅ Correct❓ Not supported by the text🛸 Out of scope🔁 Just repeats the passage

Guess the trap behind each option, then tap to check. Wrong options fail in a handful of predictable ways.

⚠️ A true description is not always a flaw

Option D describes the argument perfectly and is still wrong. A flaw option must name a mistake: fixing it should make the argument better.

Can you describe these gaps? Worked examples

✍️ Worked example Warm-up ⏱ 25 sec

The 90-year-old uncle

Rohan: "My uncle smoked for forty years and lived to 90. So smoking isn't really harmful." Which describes the flaw?

1
Split: evidence = one uncle; conclusion = smoking isn't harmful.
2
Describe: "one exception used to deny a pattern across millions".
3
Match: "relies on a single case to dismiss a general finding".
4
Confirm: he did rely on one case, and more cases would fix it. A real mistake.

Answer: It uses one exception to reject a general pattern.

⚡ The exam-hall shortcut

"How many cases?" One, for a claim about everyone: the gap is sample size.

✍️ Worked example CLAT level ⏱ 40 sec

The moot team

"To be picked for the moot team, a student must have attended the research workshop. Meher attended it, so she will be picked." The argument is flawed because it… (A) treats something required for selection as a guarantee of selection; (B) assumes the workshop was useful; (C) attacks Meher's character; (D) relies on an unrepresentative sample.

1
Split: evidence = the workshop is required, Meher attended; conclusion = she'll be picked.
2
Describe: "needed, so treated as enough".
3
Match: A. B is beside the point; C and D aren't present.
4
Confirm: "must have" means required, never guaranteed.

Answer: A

⚡ The exam-hall shortcut

"Must" is a ticket to the queue, not a seat. Spot must / only if / required and check for a promise.

✍️ Worked example Passage ⏱ 70 sec

The four-day week (passage-length)

"Last year, twelve private schools in the state moved to a four-day week. By the year's end their average board results had risen by six per cent, and parents reported happier children. The lesson is obvious. The education department should move all 4,000 government schools to a four-day week from next session, because a shorter week clearly improves results."
The reasoning is most vulnerable to the criticism that it… (A) assumes results from a small group of private schools that chose to switch will be repeated in very different government schools; (B) ignores that parents' reports may be biased; (C) fails to show that a four-day week saves money; (D) relies on results that are too old.

1
Split: evidence = 12 private schools, results up 6%; conclusion = all 4,000 government schools should switch.
2
Describe: "twelve self-selected private schools stand in for 4,000 government ones". Schools that chose to switch may differ in money, staff and pupils.
3
Match: A. B hits the parents' reports, but the conclusion rests on results. C: money is never claimed. D: the data is last year's.
4
Confirm: he does generalise across very different schools; a government-school trial would fix it.

Answer: A: an unrepresentative sample stretched to a much bigger, different group.

⚡ The exam-hall shortcut

Evidence group (12 private) vs conclusion group (4,000 government): a mismatch is the gap.

How has CLAT asked flaw-style questions?

📝 Asked in CLAT 2025 · Q107 Spot the unsupported claim

…India now reports the highest growth of ultra-processed food consumption among the youth, as well as low levels of exercise and adequate sleep. Cultural changes, including smartphones and a preponderance of English in schools, are also associated with weakened family relationships… Recent findings based on a large database of over 1,50,000 individuals in India are beginning to shed light on the correlates of mental well-being among adolescents. The findings are dire… Previous studies have found that ownership of smartphones is "frying" the brain. Data also suggests that it is not merely the ownership of a phone but also the early age of access that is associated with worse cognition and mental well-being as young adults… Recent data globally and from India shows a strong association between the consumption of ultra-processed foods and poor mental well-being, particularly the capacities for emotional and cognitive control. [Adapted from V. Anantha Nageswaran and Shailender Swaminathan, The Indian Express, September 7, 2024]

Which of the following statements by the author lack credible evidence in the passage?

AExcessive mobile usage linked to mental health issues

BProviding mobiles to adolescents resulting in mental stress

CStudents learning the English language have weakened family relationships

DInadequate sleep and junk food resulting in mental distress

Reveal answer + reasoning

Answer: C

The describe step turned into a hunt: for each claim, ask what the author puts behind it. Phones: "previous studies" and "data also suggests". Early access: data on age of access. Junk food and lifestyle: a 1,50,000-person database and "recent data". English and family ties: one sentence saying they are "associated", with no study, data or source. Simply asserted. Answer C. Time: 40 seconds.

Why the others fail

A — Backed by "previous studies" on smartphone ownership.
B — Backed by data on the early age of access to phones.
D — Backed by the large database on lifestyle and the data on ultra-processed food.

🧪 CLAT-style practice (not a past question) Describe, then match

Last year a university moved its semester exams online. The pass rate jumped from 71 per cent to 89 per cent. This proves that online exams measure a student's real ability far better than paper exams, because students are no longer crushed by the stress of a silent hall and a ticking clock. Some argue that a pass rate is a crude measure, but no measure is perfect. Every university in the country should follow this example and move its exams online from the next semester.

Which of the following best describes a flaw in the author's reasoning?

AIt assumes the higher pass rate reflects better measurement of ability, without ruling out that the online exams were simply easier to pass

BIt relies on data from too many universities

CIt presents only two exam formats when several exist

DIt treats students' opinions as facts

Reveal answer + reasoning

Answer: A

Split: evidence = pass rate up at one university; conclusion = online exams measure ability better. Describe: "a higher pass rate is read as better measurement; it may just be an easier test". Match: A. Confirm: the author never rules it out.

Why the others fail

B — Opposite: one university.
C — Two formats are compared, but nothing depends on there being only two.
D — No student opinions are quoted.

Which flaw myths cost students marks?

💥 Myth vs fact

Myth vs fact: flaw questions

🙅 Myth

You need to memorise twenty fallacy names.

Tap to bust it →

✅ Fact

Options describe in plain words. A five-word description of the gap beats a label.

🙅 Myth

If an option accurately describes the argument, it's the flaw.

Tap to bust it →

✅ Fact

It must also be a mistake. Accurate-but-harmless is a classic trap.

🙅 Myth

The flaw is that the conclusion is false.

Tap to bust it →

✅ Fact

A flawed argument can reach a true conclusion. You judge the support, not the claim.

Quick quiz: describe it, then match it

🎯 Quick quiz

Five gaps to describe

0 / 5

A food blogger writes: "The new café on Mall Road opened on Sunday and already has twenty-five online reviews, every single one five stars. Several reviewers posted photos from the opening-day party they were invited to. With a perfect score like that, it is clearly the best café in the city, and anyone who disagrees simply hasn't been there yet."

Q1. The blogger's reasoning is flawed because it…

Q2. Which of these is a FLAW option rather than a WEAKEN option?

Q3. "The coach called Meher a natural debater. Natural abilities don't need training. So Meher needn't practise." The flaw?

In September the hostel cut Wi-Fi at 10 pm. By October, attendance at 8 am lectures had risen by a third. The warden concludes that the cut-off made students sleep earlier and so attend more lectures. September was also the month the college began counting attendance towards exam eligibility, and the warden now wants the cut-off moved to 9 pm.

Q4. The warden's reasoning is most vulnerable to the criticism that it…

Q5. "Sales tripled after we hired a celebrity, so the celebrity caused it." The option "It compares sales before and after the hire" fails which confirm check?

🎯 Flaw questions in a nutshell

A flaw is the gap between what the evidence shows and what the conclusion claims.
Run Split → Describe → Match → Confirm.
Write your own description before reading the options.
Flaw options describe the argument; weaken options add facts.
Confirm twice: did the author do it, and is it a mistake?

📎 Cheat sheet

"flawed because", "vulnerable to the criticism" → flaw → describe the gap, then match.
"lack credible evidence" → unsupported claim → ask what backs each claim.
"if true, most weakens" → weaken → a new fact through the same gap.
"the author assumes" → assumption → the bridge the flaw leaves unbuilt.
"same flaw as" → parallel flaw → describe it abstractly, match the shape.

Frequently asked questions

What is a flaw question in logical reasoning?

It asks what is wrong with the reasoning: why the evidence doesn't prove the conclusion. You don't argue with the conclusion. You describe the gap, such as a tiny sample, an ignored cause or a shifting word, and pick the option describing the same gap.

How is a flaw question different from a weaken question?

A flaw option describes the argument ("it assumes…", "it fails to consider…") and adds nothing new. A weaken option is a new fact you accept as true that makes the conclusion less likely. Both aim at the same gap, so describing the gap first helps with both.

Do I need to memorise fallacy names for CLAT?

No. CLAT options describe errors in plain words, and real stems never ask you to name a fallacy. Names are a useful shorthand for spotting patterns quickly, but the mark comes from matching your description of the gap to the option's description.

Does CLAT ask flaw questions?

Rarely in so many words: no 2020–25 Logical Reasoning stem uses the word flaw, and 2025 Q107 on unsupported claims is the closest. But weaken, assumption and evidence questions every year test the same skill of finding and describing the gap in an argument.