The answer is B. This is because it was during the Great Depression.
Because Britain went to war with China over questions of trade, diplomacy, national dignity and, most importantly, drug trafficking
They felt endangered because they knew that the government would try to abolish slavery.
The answer is:
Multiple civil wars
Economic collapse due to inflation
Repeated invasions from all over....
Hope I helped!!!!^-^
C, Niagara Falls is around Canada