Tobias Wolff most likely named his short story "Mortals" because the story explores the theme of people

a) coming to terms with the idea that one day they too will die
b) wanting to find out what their loved ones really think of them
c) achieving immortality by being "big people" while they are alive
d) hoping that they will have accomplished before they die

well stockyards mean a large yard containing pens and sheds, typically adjacent to a slaughterhouse, in which livestock is kept and sorted. and i'm assuming that by party you   mean a large group of people which does make sense because chicago is a very crowded place much like new york. stockyards tend to take up a lot of room due to needing the area for pens to keep animals in and the fact that stockyards are usually right by slaughterhouse where they process and distribute the product. so its much like a zoo but with some dead animal products close by.

greet them:

buenas noches.

that is considered night time which is when "good night" is used.

the answer that is correct is the last option.