The main purpose of the Lend-Lease Program was to

Aisolate the Soviet Union militarily
Battempt to convince Italy to maintain neutrality
Caid nations deemed vital to American security
Dprovide aid against communist insurgencies in Spain
Eend the Depression through wartime production

Verified Answer :

The main purpose of the Lend-Lease Program was to "(C) aid nations deemed vital to American security," since this program allowed the US to lend ships and military supplies to Britain without officially involving itself in World War II.