Final answer:
During the Cold War, the Marshall Plan was a manifestation of Containment, the Berlin Wall represented Brinkmanship and Containment, the CIA was formed for Intelligence Gathering, and Aid to Greece was an example of Containment through the implementation of the Truman Doctrine.
Step-by-step explanation:
The Marshall Plan corresponds to the strategy of Containment (B). This plan was designed to provide financial assistance to help rebuild European nations after World War II and prevent the spread of communism by economically stabilizing these countries.
The Berlin Wall was a physical manifestation of the Containment policy (B), but it also represented the concept of Brinksmanship (A), where both sides pushed the conflict to the edge of confrontation without actual warfare.
The formation of the CIA falls under the strategy of Intelligence Gathering (D). The CIA was created to collect and analyze information that could be critical in countering the Soviet Union during the Cold War.
Aid to Greece was an application of the Truman Doctrine and the strategy of Containment (B), aimed at stopping the spread of communism beyond Eastern Europe by supporting non-communist regimes.
The Domino Theory (C) is associated with events like the spread of communism in Southeast Asia, where it was feared that the fall of one nation to communism could lead to subsequent nations falling as well.