The State Department plays a pivotal role in American foreign policy by formulating and executing diplomatic strategies to advance national interests and maintain peaceful international relations. The Option D is correct.
In U.S. the State Department carries out routine diplomatic activities, such as negotiating treaties, representing the United States in international forums, and fostering cooperation with other nations.
It also coordinates various sources of national intelligence to inform foreign policy decisions, ensuring a well-informed and strategic approach.
Moreover, the State Department upholds civilian control of the military by overseeing the diplomatic aspects of national security and ensuring that the military acts in accordance with established policies and objectives.