An immediate consequence of the Tet Offensive was that C.) popular support for the war declined in the United States.
The Tet Offensive was a military offensive by the Viet Cong in South Vietnam that led to a lot of American military deaths.
As a result, there was a loss of popular support for the war in the United States as people were enraged by the loss of American lives.
In conclusion, option C is correct.
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