Which is a major source of argument between Sunni and Shia Muslims? A. whether the pope has spiritual authority

B. when Islam was founded

C. who is the rightful leader of Islam

D. whether the new testament is valid

C.) Who is the rightful leader of islam

Explanation:

One of the most crucial differences between Shia and Sunni Muslims is the importance that the Shiites give to Ali, whom the Sunni do not recognize as being the prophet's rightful successor

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