I shall be teaching him. Change It Into Passive Voice

Question: I shall be teaching him. Change It Into Passive Voice.

A) He shall be taught by me.

B) He will be taught by me.

C) He shall be being taught by me.

D) He will be being taught by me.

Answer:
D) He will be being taught by me.

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I had written the letter. (Make it into passive voice)