The correct answer is D. The bridge had been constructed by the men.
The other options are incorrect because they do not accurately reflect the tense of the sentence. Option A, “The bridge has been constructed by the men,” uses the present perfect tense, which is used to talk about actions that began in the past and continue to the present. However, the sentence is about an action that was completed in the past. Option B, “The bridge is being constructed by the men,” uses the present progressive tense, which is used to talk about actions that are happening now. However, the sentence is about an action that happened in the past. Option C, “The bridge was being constructed by the men,” uses the past progressive tense, which is used to talk about actions that were happening at a specific time in the past. However, the sentence does not specify a specific time in the past.
The sentence “The men had constructed the bridge” uses the past perfect tense, which is used to talk about actions that were completed before another action in the past. In this case, the action of constructing the bridge was completed before the action of talking about it.