Select the correct passive form of the given sentence.

Did he do his mission?

Was his mission done by him?

Let's analyze each option:

☀ Was his mission done by him?

This option is the correct passive form of the given sentence. It follows the structure where the subject "his mission" receives the action "done" by the agent "him."

☀ Was his mission do by him?

This option is not grammatically correct. The correct form should be "Was his mission done by him?"

☀ Was his mission being done by him?

This option is in the present continuous passive tense, which does not match the tense of the original sentence. The original sentence is in the past tense, and the correct passive form for it is in the past simple tense.

☀ Had his mission been done by him?

This option is in the past perfect passive tense, which is not appropriate for the original sentence. The original sentence is in the simple past tense, and the correct passive form for it is in the past simple tense.

Correct answer: ☀ Was his mission done by him?