Correct Answer: That man has been chosen by the citizens as their leader.

Solution : The first option is the correct choice.

Passive voice is the voice in which the object experiences an action rather than the person who performs the action. Hence, the object in the active voice becomes the subject in the passive voice.

The structure of the passive sentence in the present perfect tense is: Object + has + been + past participle form of the main verb + by + subject + prepositional phrase.

Therefore, the sentence in the passive voice is: That man has been chosen by the citizens as their leader.