Final answer:
The president is the only person in the United States who can declare war.
Step-by-step explanation:
The correct answer is the president. According to the Constitution of the United States, only the president has the power to declare war. This responsibility lies with the executive branch of the government, headed by the president. The president is the commander-in-chief of the military forces, which includes the power to initiate military action and declare war when necessary.
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