Please help i rlly need to ace this :( "After the death of Muhammad in 632 CE there was some controversy as to who should become the new leader of the Islamic people. Some believe that the new leader should be elected from among Muhammad's able companions. They thought future leaders should be people who had studied under the great leader. The first elected caliph Abu Bakr a close friend and advisor of Muhammad, and his position was supported by the Sunnis." who still support the idea that devout Muslims like Abu Bakr are able to lead.

What does the word caliph mean in the text?

a
highest Muslim leader
b
Muhammad's family member
c
Muslim place of worship
d
important government building