15.Psychologists Kenneth and Mamie Phipps Clark foundthat doll testsA)demonstrated that observational learning can promote aggressive as well as nurturing behavior in children. B)showed that most people are willing to obey authority figures, even if those orders conflict with their own personal values. C)confirmed that behavior can be modified based on a system of positive or negative reinforcements. D)exposed internalized racism in African-American children, particularly among children attending segregated schools

D)exposed internalized racism in African-American children, particularly among children attending segregated schools

Explanation:

Pychologists Kenneth and Mamie Phipps Clark were very famous in the psychological field as they have done various researchers and experiments. Kenneth Clark (conducted research on the "impact of racial segregation on children") was the husband of Mamie Phipps Clark (researched on "development of self-consciousness in black children"). They both were mainly famous for their experiment in which they've utilized dolls to study "children's attitude" towards race.

They concluded that the majority of the "black children" tends to prefer white dolls instead of the black dolls because children  described black dolls as bad.

In the question above, the correct answer is D.

i dont know sorry why dont you looking it up on google

permafrost layer, it exists beneath a layer of soil, rock or sediment.