Answer: The correct answer is C-the authorization for the use of the US military force in Vietnam.
Explanation: The Gulf of Tonkin Resolution was enacted August 7, 1964 and came as a result of three North Vietnam torpedo boats firing on a United States destroyer, the U.S.S. Maddox while patrolling in the Gulf of Tonkin on August 2, 1964. Five days later the US Congress approved the Resolution.