The word "firsthand" suggests that doctors did not think the sickness was yellow fever because they had not personally treated any victims. (option C)
<h3>What does "firsthand" suggest?</h3>
In the paragraph, the author says that many doctors had not encountered the disease "firsthand." Dr. Rush had, however, and he was affirming that the disease was actually yellow fever.
The contrast lies in the fact that Dr. Rush had seen cases of the disease, whereas the other doctors hadn't seen it "firsthand," that is, with their own eyes. Thus, they did not believe Dr. Rush.
With the information above in mind, we can select option C as the correct answer. Doctors did not believe Dr. Rush when he said the disease was yellow fever because they had not treated it personally.
Learn more about the meaning of words here:
brainly.com/question/2000633
