Answer:
A. They fought in segregated units in the armed forces.
The answer is B because the Mechanical Reaper changed the way the world worked at the time; It made the demand for slaves go up as the work necessitated some manual work
You didn't really provide the letter out of which we should be able to deduce the benefits. However, Crusaders would say that the benefit of the crusaders were that they regained the holy land and could also profit out of this either by looting and pillaging neighbouring muslim villages or because they thought they were closer to God this way.
The Renaissance started around 1500.
The Middle Ages started around 500 and ended around 1500. The right answer is B.
