one of the LR's was pretty rough for me and it definitely wasn't the experimental. I'm not sure if that's because it was actually tough or because it was the last section and I lost focus.

This question tripped me up because I was looking for the answer to be that bulging discs sometimes leads to back pain. I automatically eliminated B since it seemed so far off from what I was expecting. I picked D because I thought "characteristic" could refer to the argument's entire relationship between back pain and bulging discs. That relationship may have been found in half of a sample, but that doesn't mean it would occur in half of a population. It makes sense to me now that B is a much better answer, but do you have any advice on how "characteristic" is usually defined on the lsat?