In what way was the tet offensive a strategic blow to the americans?
a. the north vietnamese captured key cities in south vietnam
b. the communists proved they didn't have the ability to keep fighting
c. the south vietnamese refused to u. s. forces in the fighting.

C. The South Vietnamese refused to help U.S. forces in the fighting.

Explanation:

The Tet offensive was a military operation planned by the government of North Vietnam and executed by the North Vietnamese Army and the Vietcong in 1968, against the US-led allies, especially the Army of the Republic of Vietnam (ERVN) , Army of South Vietnam), during the Vietnam War.

The planning of the offensive was meticulous and the execution well done; but the military results were disastrous; not so the political consequences, especially in the United States. The large number of US soldiers killed during the offensive, about 14,000, was not digested by the American people. The rejection of the war in the United States increased and that meant a turn of the war towards the defeat of the coalition. Some authors consider that it was a tactical defeat, since in addition to dying tens of thousands of North Vietnamese fighters, they lost the totality of the conquered. However, it is considered to be a strategic victory due to the subsequent change that it caused in the US military strategy.

they believed democracy was worth the fight