What was the Gulf of Tokin Resolution?

Question

A) was it the beggining of the end for American involvement in Vietnam
B) declared the USSR's official entry into the war
C) gave President Johnson the right to bomb North Vietnam

Answer 1

C) it gave President Johnson the right to bomb North Vietnam.

What its first section actually said was:

"That the Congress approves and supports the determination of the President, as Commander in Chief, to take all necessary measures to repel any armed attack against the forces of the United States and to prevent further aggression."

By the way, it turned out later that the incident on which the resolution was based did not actually happen.

Answer 2

And the follow-up question: "who blew up the USS Maine?"