This question assesses the understanding of the past perfect tense, which is used to describe an action that was completed before another action in the past. The correct answer is B, as 'had gone' correctly uses the past perfect tense to indicate that the action of going to the store was completed before the realization about the forgotten wallet. Option A incorrectly uses the present perfect tense. Option C incorrectly places the past perfect tense after the simple past tense. Option D uses the present tense, which is incorrect for describing past actions.