It looks like you're new here. If you want to get involved, click one of these buttons!
The question stem for this question asks us to pick an answer choice that shows that the explanation we were given in the stimulus is only a "partial one." I was doing this question as part of my weakening problem set. I read through the stimulus and was quickly able to identify my premise and conclusion:
P: Time runner's foot spends on the surface is less on a hard surface
C: Hard surface makes for greater running speed than a soft surface
I ended up choosing answer choice B, because I thought it provided us with an alternative explanation for why runners perform faster on the hard surface. In my mind, I thought the author was neglecting to acknowledge that it was actually the height of the runners that was affecting their performance rather than the hard surface.
If I were to add the following to answer choice B:
"when running on hard surfaces"---- would this make answer choice B correct? If not, why? Or would the stimulus have to make reference to the short v. tall runners?
Admin Note: https://7sage.com/lsat_explanations/lsat-30-section-2-question-09/