What does wright mills mean by “cheerful robots

Wright Mills meant “cheerful robots'' by the Americans were not exercising their right to freedom and just being like robots

Explanation:

Wright Mills was a sociologist and always stood for equality in the society and to improve the conditions of the society. In the year 1959, he stated the words of America people being cheerful robots and by stating this he meant that the people of the United States of America were being like robots who were only listening to the officials of the government.

They were not exercising their right to question the official. They were just simply listening to what the government was saying or doing for them or not questioning the employers. Freedom of choice was not being exercised.

it further strained relations between the north and the south and convinced

option d is correct. corroborated sources of historical evidence   is necessary to validate a claim about an event in history.

historians tend to use written sources, but audio and visual materials as well as artifacts are important objects that supply information to modern historians.

historical sources are usually divided into two categories: primary and secondary sources. depending on the historian's intent, some sources shift their designation. determining what type of sources toimplement, and the level of credibility and reliability of those sources, is a significant step in critical thinking for the historian.

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