How many examples are there "as evidence of tribalism"

A．Modern African politicians approve of tribal divisions.
B．A person is usually taken care of by his own tribe.
C．Africans consider it an obligation to give a job to a fellow tribesman.
D．Tribalism is still a powerful force in day - to - day African life.

A．through carelessness.
B．because they were human beings
C．because he had a strange name
D．by pronouncing his name incorrectly