Emile Durkheim was a French sociologist who was working on structural functionalism. His focus were different social institutions and the roles they play in the society. According Durkeim the society was an organism in which each portion plays a vital role in keeping the organism stable and healthy.
Durkheim defined collective conscience as the communal beliefs, morals, and attitudes of a society.
The answer to the question is D
The Louisiana purchase was a purchase made by America from French land which is now around Louisiana and nearby states in the U.S. it relates to manifest destiny because it allowed for new settlers to move westward and inhabit new land.