The correct description of the term caliph is a Muslim ruler in the Islamic Empire. Option D is correct.
A caliph is a religious and civil leader in a Muslim country.
Caliph stems from the Arabic word khalafa, which means "successor" or "next in line." It was adopted as a title by Abu-bekr, the first Islamic leader following the death of Mohammed, the prophet who founded the religion of Islam.
All great Islamic leaders take the title caliph.
