Which legislation passed by Congress authorized the use of force in Vietnam?

A.
the Marshall Plan
B.
the National Defense Education Act
C.
the Gulf of Tonkin Resolution
D.
the War Powers Act

C. the Gulf of Tonkin Resolution

Explanation:

The resolution was passed because of the Gulf of Tonkin Incident, where the US fleet was attacked by the North Vietnamese torpedo boats in 1964. It authorized the use of force by President Lyndon B Johnson, without him actually making a formal declaration of war against the country.

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because the vietnam war was fought in an especially brutal and untraditional way