For question 13, this is an inference question that asks you to decide which one is "commonly" considered provocative. Most people would not consider puppies and babies provocative... so thinking about what would be commonly considered, in our society.
For question 20, I don't understand the book explanation, but this is how I looked at the question. I chose answer D only because of eliminating the other choices and seeing this as the "best" of 4 really bad options. Since the passage mentioned that laws "have existed.... at one time or another" as well as "the disease model..... should not be punished" in lines 20-31, that was feeble evidence for choice D. Not a strong choice, but I outright eliminated A-C.