the answer is C, Was the first foregin group to rule all of china
Due to the deaths of most of the population, "ordinary farm workers, who had been forced into serfdom previously, shot up by 50%. More bullion among a smaller population meant more wealth across all classes and because the same land was in use and it was now plentiful, it resulted in technological advances as well." - Hank Campbell (found at Science20.com)
About a third of the clergy fell to the Black Death, making answer a. unlikely.
I never found any information stating Peasants migrated into cities for medical care, making answer b. unlikely.
Lower classes benefited from the Black Death economically, therefore c. is my final answer.
Doctors at this time knew nothing about how to cure disease, they also made little to none advancements. Answer d. is very wrong.
In short, I believe Darwin's theory was controversial in the 1800s because it contradicted the biblical view of creation.
(Sorry for the shortness.)
xoxo
This question is really simple. The United States gained Guantanamo Bay, which is infamous today, for its prison.
The Guantanamo Bay Corrections Facility holds the most VIP terrorist inmates, and it's managed by the Central Intelligence Agency (CIA).