The correct answer is: B. Sunnis and Shias.
Sunnis and Shias are the two main denominations of Islam. They differ in their beliefs about who should have succeeded the Prophet Muhammad as leader of the Muslim community. Sunnis believe that the Prophet Muhammad’s close friend and confidante Abu Bakr should have been his successor, while Shias believe that the Prophet Muhammad’s cousin and son-in-law Ali should have been his successor.
Sunnis make up the majority of Muslims in the world, while Shias make up a minority. The two groups have been in conflict with each other for centuries. The most recent major conflict between Sunnis and Shias was the Syrian Civil War, which began in 2011.
The other options are incorrect. Catholics and Protestants are the two main denominations of Christianity. Mahayana and Hinayan are two schools of Buddhism.