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Most LSAT wrong answers are wrong because they overreach. So students train themselves to flinch at absolute language — all, every, must, guarantees. Useful habit, except on one question type where that instinct actively costs points: sufficient assumption questions.

You'll recognize the stems: "The conclusion follows logically if which one of the following is assumed?" or "Which one of the following, if assumed, allows the conclusion to be properly drawn?"

The job is to find an answer that guarantees the conclusion. Not supports it. Guarantees it. If the correct answer is true, you cannot deny the conclusion without contradicting yourself.

That makes these the mirror image of necessary assumption questions, which ask for the bare minimum an argument needs. A sufficient assumption fills the entire logical gap in one move — even if it does far more than the argument strictly requires.

So the real skill is locating the gap. The fastest way: find a term in the conclusion that never appears in the premises. A new term in the conclusion means the argument never connected it to the evidence, and that missing connection is the gap.

Example. A city ordinance requires any restaurant that serves raw fish to hold a special permit. Kenji's food truck serves raw fish. Therefore, Kenji's food truck needs the permit. The rule is about restaurants; the evidence is about a food truck. The gap is whether a food truck counts as a restaurant under the ordinance. The sufficient assumption closes it directly: "Kenji's food truck qualifies as a restaurant under the ordinance." Once that is true, the conclusion is locked in.

And notice: "Every food truck in the city qualifies as a restaurant under the ordinance" works too. It is complete overkill — and still correct, because overkill still guarantees the conclusion. This is why the "too strong" reflex backfires here. On sufficient assumption questions, the absolute-sounding answer is often exactly right.

Two traps to avoid. First, strengtheners: an answer that makes the conclusion more likely but not certain is not sufficient. If your answer leaves the conclusion at "probably," keep looking. Second, the negation test — that tool belongs to necessary assumption questions and does not reliably work here. The right test is simpler: assume the answer is true and try to derive the conclusion. If it follows with certainty, you have your answer.

Find the new term, close the gap completely, and stop penalizing answers for being strong.

Most LSAT questions ask you to judge an argument. Sufficient assumption questions ask you to repair one.

You get an argument with a hole in it, and your job is to find the answer that, if true, makes the conclusion follow with certainty. Not "helps the argument." Not "makes it more convincing." Guarantees it. You'll recognize the stem: "The conclusion follows logically if which one of the following is assumed?"

The whole skill comes down to finding the gap.

Every one of these arguments is missing a link between the evidence and the conclusion. The most common version: a term shows up in the conclusion that the premises never established.

Try it: The museum offers free admission to all city residents. Dana lives in Riverside. So Dana gets free admission.

The premises talk about city residents and about Riverside. The conclusion treats those as connected, but nothing on the page says they are. That's the gap: is Riverside in the city? The right answer closes it — "Everyone who lives in Riverside is a city resident." Add that, and denying the conclusion becomes a contradiction.

That gives you the test for every answer choice: if this is true, can I derive the conclusion, full stop? If your honest answer is "probably," you're holding a strengthener, not a sufficient assumption. The bar is certainty.

Three habits worth breaking:

Rejecting answers for sounding too strong. On most question types, "all" and "every" are warning signs. Here they're often the point. An answer can't fully close a logical gap while hedging.

Reaching for the negation test. That tool belongs to necessary assumption questions. Negating answer choices won't reliably sort sufficient assumptions — use the direct test instead: does this guarantee the conclusion?

Closing the wrong gap. Misread what's missing and you'll hunt for an answer that solves a problem the argument doesn't have. Reread the conclusion first, then ask what someone would need to believe to accept it from this evidence alone.

Keep the two assumption types straight: necessary is the minimum the argument needs; sufficient is enough to lock the conclusion in place. Different bar, different test, different answers.