The correct answer is B. went.
The sentence is in the past tense, so the verb must also be in the past tense. The other options are not in the past tense.
A. was going is in the past progressive tense, which is used to describe an action that was in progress at a specific time in the past. In this case, the action is not in progress at a specific time in the past, so this option is not correct.
C. have gone is in the present perfect tense, which is used to describe an action that has been completed or an event that has happened at an unspecified time in the past. In this case, the action is not completed or an event that has happened at an unspecified time in the past, so this option is not correct.
D. had gone is in the past perfect tense, which is used to describe an action that was completed before another action in the past. In this case, there is no other action in the past, so this option is not correct.
E. am going is in the present tense, which is used to describe an action that is happening now or an event that will happen in the future. In this case, the action is not happening now or an event that will happen in the future, so this option is not correct.