What Event Prompted President Johnson to Appeal to Congress to Pass

What event prompted President Johnson to appeal to Congress to pass the Gulf of Tonkin resolution?

A) the suicide bombing at the U.S. military base at Pleiku
B) alleged attacks against U.S. destroyers by North Vietnamese patrol boats
C) the surprise attack launched by North Vietnam and the Vietcong on Tet, the Vietnamese lunar New Year holiday
D) the search-and-destroy mission by American troops that resulted in the My Lai Massacre