Is anyone else worried about knowing the definition/ meaning of words used?? (expedient in this case)

I have to google definitions at least 5 times every time i do a practice test. Not sure how to get around this weakness as each LSAT is obviously going to have different verbiage 

I got this question right during a 'You Try" question of the lesson- then it appears in this review drill- I select the same answer choice- and it is wrong?

The simpler version of (A) would have been "Walker is a polarizing figure"

What?? How?? How did they get to that??

I feel like I'm living in an alternate universe when I read some of these explanations...