Why (E) is right: supporting a generalization
A Strengthen explanation from our free library. The question below is original, written for this page. Then the full breakdown: why the right answer is right, and why each wrong answer is wrong.
The question
A survey of 200 marathon runners found that those who trained with music finished faster than those who trained without it. Coach Reyes concludes that training with music improves race performance for runners in general.
Which one of the following, if true, most strengthens Coach Reyes's conclusion?
- The runners who trained with music also tended to follow stricter diets.
- Many elite runners train without music.
- Music has also been shown to improve performance in cycling.
- The survey covered runners across a full racing season.
- The 200 runners surveyed matched the broader running population in age, experience, and ability. Correct
Why (E) is correct
The conclusion jumps from 200 surveyed runners to runners in general. That jump is safe only if the 200 are like runners in general. Choice (E) says they are.
It closes the exact gap between the evidence and the conclusion. The other choices either attack the conclusion or answer a question nobody asked.
Why the wrong answers are wrong
(A) Reversed: it weakens
This hands the skeptic an alternative cause. Maybe the diet, not the music, made them faster. That weakens the conclusion.
(B) Reversed: it weakens
If elite runners skip music and still run fast, music looks less important. Again the wrong direction for a strengthen question.
(C) Out of scope
Cycling is a different sport. What helps cyclists need not help runners, and the conclusion is only about runners.
(D) Half-right
A full season rules out a fluke month, but the conclusion is about runners in general. The gap is who was surveyed, not when.
Last updated October 12, 2026