The timeline shows that the first U.S. combat troops in Vietnam landed a year after the Gulf of Tonkin Resolution.
What was the Gulf of Tonkin incident?
This was an event where a U.S. navy vessel was attacked off the waters of North Vietnam which convinced Congress of the need for military action.
As a result, the U.S. began bombing Vietnam and a year later in 1965, the first U.S. combat troops landed in Vietnam.
In conclusion, option B is correct.
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