Which invention improved Mayan agricultural methods? the relief
the codex
the 365-day calendar
the concept of zero

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:

answer: which of the following best describes greek tragedy?

a) it was lighthearted and included songs and elaborate costumes.

b) the plays included political statement that mocked leaders and their policies.

c) the lead character suffers because of personal flaw.

d) the gods intervene negatively in the lives of men.

the answer would be d

explanation:

nothing did. japan is wierd and always was.