Muhammad and his followers returned to Mecca and
A. claimed it for Islam
B. spread their teachings
C. destroyed the Ka'bah idols
D. all of the above

D  I've done this

Explanation:

        i'm fairly sure that the correct answers are 2 and 3.

        i used both my knowledge of world history and the process of elimination to obtain these answers. option 1 cannot be a possible selection because the mandate of heaven belongs to ancient chinese philosophical belief. option 4 sounds like it would benefit the region than detriment it. however, both 2 and 3 explain a potential reason for what could have contributed to the fall of the roman empire.

      hope this ! if i were you, i'd get a second opinion, because i haven't taken this course for a year. best of luck!

***websites that me understand the curriculum better last year are and ***

the steam engine.

the locomotive.

the telephone.

the telegraph.

the internal combustion engine.

the rifle.

ironclad ships.

electricity/light bulb.