The french the patriot war effort by a. attacking the main island of britain to distract british forces. b. keeping spain out of the war. c. going to war against hostile native american groups. end of exam d. providing a navy and military support.

France was happy to assist the United States, due both to an appreciation for the values behind the Declaration of Independence and a long-standing rivalry with the British.
To this end, the French provided the Patriots with funding, weapons, and even a small army unit to assist in the fight against the British. The French also provided a navy which proved to be instrumental in several battles. 

D) Providing a navy and military support.