Choose the grammatically correct sentence from the given options.

The correct answer is Option (3) → Never will I see him again.

Inversion after a negative adverb:

• When a negative or limiting word such as never, seldom, rarely, hardly or not only begins a sentence, the word order changes as in a question.
• Pattern: negative adverb + helping verb + subject + main verb
  • Negative adverb: Never
  • Helping verb: will
  • Subject: I
  • Main verb: see him again
• Without inversion the same idea reads "I will never see him again".
  Example: Never have I seen such a beautiful sunset.

Why the Other Options are Incorrect?

Option 1: Never I'll see him again. — Incorrect. "Never" begins the sentence, but the helping verb is not moved before the subject; it should be "Never will I".
Corrected: Never will I see him again.

Option 2: I'll not see him never again. — Incorrect. It is a double negative: "not" and "never" in the same clause. Standard English uses one negative: "I'll never see him again".
Corrected: I'll never see him again.

Option 4: I'll see him again never. — Incorrect. "Never" is an adverb of frequency; it goes before the main verb, not at the end of the sentence.
Corrected: I'll never see him again.