Which of the following illustrates a foreign policy duty of congress? negotiating a peace treaty with a rival nation declaring war on an enemy nation sending an operative to gather information about an enemy nation appointing an ambassador to improve relationships with rival nations

The correct answer is: Declaring war on an enemy nation.

Foreign policy in the United States of America is the result of a complex process, in which the decisions are shared between the Executive power (the President) and the Legislative power (the Congress). The Congress of the United States has the power, under the United States Constitution, to declare war, but the President can send military troops to an enemy area for a period of maximum sixty days without the Congress approval.

Congress can also authorize the funds for the military troops setting, with this, restrictions on the time the military troops spend during an international crisis. Some of the United States Congress' approvals on wars or international confrontations are: the Vietnam War, the Gulf War (1991), the Invasion of Iraq (2003), and the most important World War II.

The correct answer is B) declaring war on an enemy nation.

The option that illustrates a foreign policy duty of Congress is "declaring war on an enemy nation."

You can find this on Article I of the United States Constitution which enumerates the powers of Congress regarding foreign affairs, For instance, the power to declare war to other nation, as happened when President Woodrow Wilson asked Congress to enter World War I in 1917, or when President Franklin D. Roosevelt asked Congress to enter World War II in 1941. Congress also has the power to raise an army and regulate foreign trade.