The actual carrying out, or implementation, of foreign policy falls to
the president.
executive agencies.
the state department.
congress.

The actual carrying out, or implementation, of foreign policy falls to  the State Department.

Explanation:

The State Department was established in 1789 as the first department of the US government. The American constitution of 1787 gave the president direct authority to maintain relations with other nations. However, on July 21, 1789, the Congress decided to establish a Department of Foreign Affairs with Thomas Jefferson as minister.

The name was changed to Department of State in September 1789. The powers of the department were also extended with various domestic tasks, including the censuses, the currency and the management of the United States big seal. The majority of these tasks were later transferred to other ministries.

The current duties of the State Department include:

-Managing the American embassies and consulates and corps of diplomats

-Protecting US citizens abroad

-Assisting American companies in the international market

-Coordinate the international activities of other US government departments