The correct answer is A. By cementing Western European military alliances to defend against aggression.
The Marshall Plan was implemented by the United States in 1948 to provide economic support to Western European countries to help them rebuild after World War II. This initiative aimed to strengthen these nations economically and politically, thereby preventing the spread of communism and supporting the policy of containment against the Soviet Union. By promoting stability and prosperity in Western Europe, the U.S. sought to secure its allies and reduce the influence of the Soviet Union in the region.