Even though there are no choices in your question, here is some information that will help.
The Gulf of Tonkin Resolution was passed by the United States Congress on August 7, 1964. This allowed US President Lyndon B. Johnson to take any measures he wants in order to repel any attack against the US army and to use force however he wants to stop future aggression in Vietnam. This resolution essentially allows the president to send as much troops as he wants. Along with this, he can use whatever weapons/technology he wants. This gives the president a significant amount of power.