The correct answer is United States departments of State, Treasury and Defense.
The President's Cabinet is made up of 15 main executive departments. The top three departments ( in order to succession to the Presidency ) are The Department of State, The Department of Treasury and The Department of Defense.
<em>The Department of State </em>advises the Presidents and conducts international relations. It handles the relationships with foreign countries and discusses matters associated with national and foreign security and national and foreign policies.
<em>The Department of Treasury</em> manages government revenue. It collects all the federal taxes, prints all paper currency and supervises U.S. debts instruments and fiscal policy. It ensures the country's financial security.
<em>The Department of Defense</em> provides the military to protect the country. It deals directly with national security and the United Stated Arms Forces. It is the government's largest agency.