Answer:
Correct answer is B. To give nobles land in exchange for military service.
Step-by-step explanation:
Option A is not correct as this was the role of knights.
Option B is correct as they gave land to their vassals who pledge loyalty and military service to them.
Option C is not correct as they had good relations with Church, which would be endangered in this manner.
Option D is not correct as most of the people in a manor didn't know even how to read or write.