LSAT Necessary Assumption Practice Question: Track Record
An original necessary assumption question from our free Question of the Day rotation, built around a trap the LSAT reuses constantly: track record. Try it first, then read the explanation — it teaches the move, not just the answer.
Your job:Find what the argument must be assuming.
Renata has completed every mural she has begun in her twenty-year career, always by the promised date. The Dockside Arts Council has commissioned her to paint a mural on the harbor breakwater by the end of August. The council's newsletter assures readers that the breakwater mural will be finished on time.
The newsletter's argument depends on the assumption that
Show the answer & full explanation
The correct answer is D
The JBDM line
Just because she has always finished on time doesn't mean this one will be finished on time.
The maybes
- MaybeMaybe painting on a breakwater means tides and weather her studio walls never posed.
- MaybeMaybe this commission is triple the size of anything she's done.
Why D is right
Track-record arguments assume the next case resembles the past cases. Negate this answer — suppose the breakwater DOES differ in some way that prevents on-time completion — and the twenty-year record becomes irrelevant. Argument dead. Soft, past-facing, and required: textbook necessary assumption.
Why the others are wrong
- AShe doesn't need to be the best available, just on time.
- BHer future career beyond this mural is irrelevant to this deadline.
- CA prior relationship with the council isn't needed for the record to apply.
- EWhether other artists could do it has no bearing on whether she will.
Sammy's note
Track records only transfer if the next case is like the last ones. That quiet 'it's like the others' is the assumption.
What's a JBDM line?
Just Because Doesn't Mean (JBDM) is the Burton Method's foundational framework for attacking LSAT arguments: identify the premise, identify the conclusion, then say "just because [premise] doesn't mean [conclusion]" and generate "maybes" — alternative explanations that expose the gap between them. That gap is what weaken, flaw, strengthen, and assumption questions all test, so every explanation on this page starts with the JBDM line. It's a micro-lesson in the system, not just an answer key.
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Answer today's question and start a streak — then see how Sammy teaches the whole system, JBDM included, in a free lesson.