The correct option is C The Eisenhower Doctrine
The Eisenhower Doctrine, a country could request American economic assistance and/or aid from U.S. military forces if it was being threatened by armed aggression from another state. Eisenhower singled out the Soviet threat in his doctrine by authorizing the commitment of U.S. forces “to secure and protect the territorial integrity and political independence of such nations, requesting such aid against overt armed aggression from any nation controlled by international communism.