What was the main issue that drove islam to split into two groups? be sure to name the two groups.

The two groups are the Shia Muslims and the Sunni Muslims. Their beliefs differed because one group believed that Muhammad's successor should be someone from his family, while the other group believed that his successor should be chosen by the people.

The snow had blocked up his window. why because it involves pronouns like he,him,his,himself, she,her