The answer to #13 is C because the studies show that people are more likely to intervene in physical, threatening conflicts rather than in a robbery.
The answer to #14 is D due to the fact that the killer repeatedly came back when he realized Kitty was still alone. He had originally retreated to his car when a witness shouted at him, and he fled the second time, but in both instances the murderer came back to finish her.
The answer to #15 is most likely B because the article states that bystanders are less likely to get involved when they're in a group (so A and D don't make sense) and it also says that people are less likely to get involved when the conflict occurs between family, specifically husband & wife (but this could also be father-son) so C is cancelled too.
The answer to #16 is C because the author informs the reader about the many different factors, but they also persuade the reader to take action at the end of the article.
The only one I'm not 100% sure about is 15, but I think it's right given the evidence. Hope this helps!
