Editorial: The gates at most railroad crossings, while they give clear warning of oncoming trains, are not large enough to prevent automobile drivers from going around them onto the tracks. Some people claim that the ensuing accidents are partly the fault of the railroad company, but this is a mistake. Granted, if but a licensed driver is a capable adult who should know better.
What this question is testing
Your task
Find the assumption that, if added, guarantees the conclusion follows.
Common trap
Answers that only partly bridge the gap, leaving the conclusion unproven.
Winning move
Identify the new term in the conclusion and pick the choice that links it to the evidence.
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