During World War I, the Germans sent a telegram to Mexico asking them to join in fighting against the United States. In return for Mexico's participation, the victorious Germans would have given to Mexico: A.)the southwestern United States
B.)favorable trading rights to central Europe
C.)the western Caribbean islands
D.)unrestricted access to the Panama Canal

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:

c. troops marched forward in close formation against newer, more accurate weapons