I would estimate that the first one is the answer.
I looked up the summary(s) for both the passages, and 'to build a fire' is about a guy who despite everything being against him, being persistent and dying because of his actions, while 'gumption' is about the hardships of african americans.
Of course, this is just my estimation.
Im going with D it just feels right if im wrong correct me!
You can use the synonym clue in understanding the meaning of the underlined word. The other word synonymous to it might be more familiar to you so it would be a lot easier. The synonym clue says the word in a simple way.