C. by stating that the U.S. will play an active role in fighting groups that are opposed to freedom, and by supporting groups that are fighting for freedom
In the text, Kennedy says, "Let every nation know, whether it wishes us well or ill, that we shall pay any price, bear any burden, meet any hardship, support any friend, oppose any foe to assure the survival and the success of liberty" (Paragraph 5). This piece of evidence specifically tells every nation that the U.S. will do anything in it's power "to assure the survival and the success of liberty". He lists the lengths that the U.S. will go to: fighting those that are against freedom, and supporting those who are for it.