In the beginning, joseph mccarthy focused an investigation into communism's influence on what area of american life?
entertainment and broadcasting
travel and tourism
government and security
finance and investment

The correct answer is government and security.

McCarthy made national headlines when he first accused over 200 members of the State Department of being communists. At the time of these accusations (aka the 1950's) the fear of communism was widespread in America. This was due to the United States rivalry with the Soviet Union for global influence. This rivalry was a result of World War II.

McCarthy used this fear to create investigative hearings, lead by Congress, that would call suspected communists to the stand in order to answer questions about their political affiliations or connections to the Soviet Union.

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.

explanation:

abraham lincoln