What was truman’s justification for dropping the atomic bomb first on hiroshima and then again on nagasaki three days later? a. japan deserved to be bombed just as they bombed pearl harbor. b. he was saving american lives and the dropping of the atomic bombs was the quickest end. c. without the dropping of the atomic bombs the united states would lose the war. !

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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