http://7sage.com/lsat_explanations/lsat-71-section-3-question-21/
I've figured out why C) and E) are wrong, but I'm not sure how the other incorrect answers weaken the argument.
Is anyone in the Edmonton, Alberta, Canada region?
I'm taking the October 2015 test (retake) and I'll be looking for some study buddies on the weekends! Let me know :) you can respond or e-mail me at harrismegan@live.ca.