Why were there no decisive battles that ended world war 1 w

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:

yes

explanation:

the fighting words doctrine, in united states constitutional law, is a limitation to freedom of speech as protected by the first amendment to the united states constitution. in 1942, the u.s. supreme court established the doctrine by a 9–0 decision in chaplinsky v. new hampshire.

b. ensure mutual protection from communism.

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