Which statement describes a characteristic of East Africa?

Options:
It’s mountainous region made East Africa difficult to protect itself from invaders
After Christianity came to the region, Islam was no longer practiced after the 1000s
Through trade, East Africa became a multicultural mix of diverse cultures
East Africans produced cotton and grain that they traded for slaves from the Middle East

The statement that describes a characteristic of East Africa is: Through trade, East Africa became a multicultural mix of diverse cultures.