Which of the following was not a cause of conflict between american indians and the new nation during washingtons presidency?

a. continued british military presence on frontier outposts

b. disputes over land claims since the end of the revolution

c. spanish control of navigation and trade along interior rivers

d. lack of guidelines for their relationship in the constitution

The Spanish control of navigation and trade along interior rivers was not a cause of conflict between American Indians and the new nation during Washington's presidency for these activities is not an issue at all.

Moreover, most conflict resulted from continued British military presence on frontier outpost, cultural clashes, land disputes claims since the end of revolution, lack of constitution guidelines and criminal acts committed on both sides.