All the communications and military satellites would be gone, shot down and destroyed. Most of the world's power grid would have failed due to EMP bombs.
Because it was rough time.
Because their society is unstable. They allow anyone and everyone in from many different cultures. Hence the cradle part.
The first is the best option.
It is true that a lot of cultural aspects of Africa have been lost, most specifically, religion.
If we look at imperialism, its height came after the main period of African slave trade (second answer is false).
The tribal conflicts are still very ripe in Africa, and often they're fueled by the carefulness boundary drawing of countries in Africa- the third answer is false.
More self-rule is also false, if anything, imperialism brought less self-rule
