After the tet offensive, secretary of defense clark clifford believed that sending more troops to vietnam would lead to victory decrease the number of draftees require raising taxes decrease casualties in the field

The correct answer is requiring raising taxes.  

After the Tet Offensive, Secretary of Defense Clark Clifford believed that sending more troops to Vietnam would require increasing taxes.

The Tet Offensive is the name for the North Vietnamese attacks to almost 100 places of South Vietnam, on January 31, 1968. The attack broke the stalemate in Vietnam and angered people in South Vietnam and in the United States because a Viet Cong platoon attacked the U.S. Embassy in Saigon. After the attacks, Secretary of Defense Clark Clifford believed that sending more troops to Vietnam would require increasing taxes.