Sufi Muslims taught A that Muhammad was God.
B that people should live a simple life.
C that Muhammad was a teacher, but not a prophet.
D that the decision of the people was final.

C. That Muhammad was a teacher but not a prophet

Explanation:

He spread the work of 1 god but were not gonna call himself a prophet. He would often not allow people to take paintings of him as he said he didn't want to feel like a god or praised like one.

its main object was the establishment of "settlement houses" in poor urban areas, in which volunteer middle-class "settlement workers" would live, hoping to share knowledge and culture with, and alleviate the poverty of, their low-income neighbors.