Which of these contributed to the crash of 1929 and the great depression? a. stock market speculation b. the effects of world war ii eliminate c. success of the u. s. farm economy d. foreign boycotts of u. s. products?

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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