The answer for this question is (d)
The middle class I'm pretty sure
Answer:
cause and effect relationship
Explanation:
A causal relationship, also called cause and effect relationship, occurs when two events are related because a first event has a direct influence on another, in other words, because a first event causes the other to happen
{found in brainly}
Answer:
Because that is where scientists believe the first humans originated from, and where the earliest civilizations started.