Which of the following reformers believed that there should be no separation between politics and religion? a. martin luther b. john calvin c. ulrich zwingli d. john of leyden which of the following words best describes how the technical quality of paintings changed as the middle ages progressed? a. declined b. improved c. stagnated d. fluctuated

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:

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