The correct answer is option C: someone diagnosed with smallpox.
The person that would have been most grateful for the work of 19th-century scientist Edward Jenner, would be someone diagnosed with smallpox because Jenner was who discovered the first vaccine against the smallpox virus. Moreover, this disease that was widely spread in the 18th century and killed many people.
D is the answer ( for cutting off our trade with parts of the world )
<span>President Eisenhower wanted to contain communism to protect the entire region.</span>
