Answer:
Arabs come into North Africa.
All of North Africa comes under Muslim rule.
The gold-salt trade flourishes on the trans-Saharan route.
Islam spreads to Western and Southern Africa.
Step-by-step explanation:
Before the Arab people came to North Africa, several kingdoms had already developed in sub-Saharan Africa. However, contact with them was relatively limited. The Arabs came into North Africa in the 7th century CE, and over the next few years, they were able to bring all of North Africa under Muslim rule. This allowed them to conduct trade on the trans-Saharan route, helping it flourish. As the trade developed, it also carried Islam with it, until the religion eventually reached Western and Southern Africa.