Answer:
I could be either b or d. I would put D because the narrator feels confident that Columbia would accept them.
Explanation:
I believe he tracked how people were getting affected it was the very dirty conditions he took to hospitals and places where people were sick to see if they had ever been exposed to the inhumane conditions that caused Cholera
The answer is d the tone of a research paper requires a stilted, formal type of writing using only long , complex sentences to describe evidence from many sources.
