Used different types of sources to learn about the past. (a) Indians
(b) Americans
(c) Historians
(d) Portugese​

The answer is C (Historians) hope this helps:)

France played a key role in the american revolutionary war (american war of independence; 1775–1783). motivated by the ideals of the new nation which were inspired by the french enlightenment, as well as its long-term rivalry with britain and so as to avenge their territorial losses during the french and indian war, france secretly began sending supplies to the americans in 1775.