Final answer:
The first ruler of the Muslim Empire was not Muhammad but his close companion Abu Bakr, the first caliph. The term 'Jihad' in the question option is a misnomer and is not the name of a person. Abu Bakr was succeeded by the Rashidun caliphs Umar, Uthman, and Ali.
Step-by-step explanation:
The first ruler of the Muslim Empire was not Muhammad, as he was a prophet and a religious leader, not a political ruler. After his passing, the leadership passed to his close companions who were known as caliphs. Therefore, the correct answer is a) Jihad, which however is not a person but a term used within Islam. It is important to correct the option provided and identify the first caliph and true ruler, Abu Bakr, who was the father-in-law of Muhammad and one of his closest companions. Abu Bakr became the first caliph after Muhammad's death in 632 CE and was succeeded by Umar, Uthman, and Ali, all part of the 'rightly guided' or Rashidun caliphs.As for the multiple-choice options, the other names listed relevance in different contexts. Constantine was a Roman Emperor and not associated with the Muslim Empire; Muhammad is the Prophet but not a ruler; and Abraham is a patriarch in the monotheistic faiths, not a Muslim ruler.Conclusion The confusion may arise from option Jihad being listed, which is a term that in its broad meaning refers to striving or struggling, especially with a praiseworthy aim. But when it comes to identifying the first political ruler of the Muslim Empire, we should look towards Abu Bakr, the first caliph, rather than the Prophet Muhammad or the term 'Jihad'.