Security dilemma: This concept refers to the situation where one nation’s efforts to enhance its security creates security concerns for another nation with any prior intention. For example, in the Cold War era, developing nuclear weapons cause a security dilemma, which had almost resulted in a new world war in the early 1960s. This dilemma has been further manifested in the international arena with increasing military technologies, arms races, and deterrent national policies. In an attempt to solve this dilemma, nations resorted to such policies as arms control, disarmament, reduction or elimination of certain weapons as well as diplomatic efforts to reach a consensus on international security issues. Therefore, the correct option is A.