Answer:
The Sierra Madre mountains surround city & trap in polluted air.
Explanation:
I think C, sorry if I am wrong
Answer: Cohort effects.
Explanation:
The influence that one's date and place of birth has on social research is known as the cohort effect and it refers to the similarities in experiences and social influences across a particular age group.
African countries struggled after their independence because they were usually owned by empires, and then when the empires left them, the poverty and violence rised.
Im guessing its manipulation. <span />