Answer:
What was wanted by him?
Step-by-step explanation:
The passive voice is a grammatical construction in which the subject of a sentence is no longer the agent performing the action, but rather the recipient of the action. In the sentence "What did he want?", the subject is "he" and the verb is "want." In the passive version, "What was wanted by him?", the subject becomes "what" and the verb becomes "was wanted." The agent, or the person performing the action, is mentioned in a prepositional phrase at the end of the sentence. The passive voice is often used to emphasize the object or result of the action rather than the subject or agent.