What happened after seven Southern states seceded from the Union? A. The American Civil War began.
B. Abraham Lincoln was elected president.
C. Vermont abolished slavery in its constitution.
D. The North began a process of industrialization.

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:

mickey : )

explanation:

why not?

profound political, administrative, and social changes in the british isles.

this is true hope this

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