Logical Reasoning · Main Conclusion

PrepTest 128 · Section 2 · Question 13

Phase 1 (your first ~400 questions): read the guidance, then answer. No clock.

Step 1 · Pre-Question Guidance · read this first

Question type

Main Conclusion

The one idea it tests

When a speaker opens with a confident claim and then explains how it happened, the opening claim is the Boss.

The basic logic

Find the sentence every other sentence is working for. A step-by-step chain of how something works is usually the Helper, and the claim that this chain was the cause is the top bun. Keep the speaker's confidence level exactly; do not soften or strengthen it.

Tiny words that decide it

“little doubt”
“since”
“thus”

Playground logic

Nadia's top bun comes first: Biscuit's tail almost surely knocked down the block tower. Everything after it (the wagging, the bumped table, the wobble) is patty, explaining how. Kevin keeps picking a link in the chain, but those are Helpers.

Step 2 · The kid story

What's Your Point, Nadia?

Kevin's giant block tower crashed while everyone was at snack. Nadia stood up. "I am nearly certain it was Biscuit's tail. When Biscuit gets excited, his tail wags hard. A hard wag thumps the table leg. A thumped table wobbles. And a wobbling table knocks over tall towers." Kevin gasped. "So your point is that tables wobble?" "No," said Nadia. "That is a step." "Your point is that tails hit tables?" "Also a step." Priya sipped her juice box. "Her point is the very first thing she said: Biscuit's tail almost surely caused the crash. Everything else explains how." Biscuit wagged proudly, and a crayon rolled off the table. Kevin pointed. "Evidence!" Lulu wrote 'Boss first, Helpers after' on her clipboard.

Step 3 · Try the model question

Nadia: I am nearly certain Biscuit's tail knocked down the block tower. When Biscuit is excited, his tail wags hard and thumps the table leg. A thumped table wobbles, and a wobbling table topples tall towers.

Which choice sums up Nadia's overall point most accurately?

Step 4 · The courtroom tale

The Case of the Flooded Basement

Mr. Whitfield faced the jury. "There is hardly any doubt the gutter caused the flood. A clogged gutter overflows. Overflow pours beside the wall. Water beside the wall seeps through cracks. Seeping water floods a basement." The young juror in the front row raised a hand. "So your main claim is that water seeps through cracks?" Judge Amari smiled. "No. That is one rung of the ladder. His main claim is the one he started with: the gutter almost certainly caused this flood. Every other sentence explains how." Mr. Whitfield bowed. "Your Honor summarized me better than I did."

Step 5 · Work the real question

Open PrepTest 128, Section 2, Question 13 in your official copy from LSAC (for example in LawHub) and read it there.

Your answer

How to apply it

Read the argument and mark the claim that the rest is trying to prove. Ask 'why should I believe that?' of each sentence; the one answered by the others is the Boss. A chain explaining how something happens is support, not the point. Match the conclusion's strength exactly, keeping its degree of certainty. Reject choices that state a single link of the chain, or that hedge or alter what the speaker actually claims.