Select the option that expresses the given sentence in passive voice.

I have not discouraged him from doing anything.

He has not been discouraged from doing anything by me.

The correct passive voice of the given sentence is He has not been discouraged from doing anything by me.

The active voice of the sentence is I have not discouraged him from doing anything. This sentence is in the present perfect tense, which is used to describe an action that has not happened yet, but may happen in the future. The passive voice of the sentence is formed by putting the subject of the active sentence after the verb "to be" and the past participle of the main verb. In this case, the subject of the active sentence is "I" and the main verb is "discourage." The past participle of "discourage" is "discouraged." So, the passive form of the sentence is He has not been discouraged from doing anything by me.

The other options are incorrect because:

• He had not been discouraged from doing anything by me. is in the past perfect tense, while the original sentence is in the present perfect tense.
• He is not discouraging from doing anything by me. is in the present continuous tense, while the original sentence is not describing an ongoing action.
• He has not discouraged from doing anything by me. is grammatically incorrect. The verb "discourage" must be in the past participle form, not the past tense form.
• He has not discouraged by me from doing anything. lacks the preposition "from."