Which of the following sentences is correctly formed?

The correct answer is Option (1) → Only after the umpire checked the replay did the batsman walk off the field.

“Only after” at the start of a sentence:

• When a sentence starts with “Only after”, the helping verb comes before the subject in the main part.
• The part right after “Only after” keeps its usual order: “the umpire checked the replay”.
• The main part “the batsman walked off” becomes did the batsman walk off.

Why the Other Options are Incorrect?

Option 2: So tired the farmers were that they slept under the neem tree after lunch. — Incorrect. The option says “So tired the farmers were”. After “So + adjective” at the start, the verb comes before the subject.
Corrected: So tired were the farmers that they slept under the neem tree after lunch.

Option 3: Kabir has been never to the Taj Mahal, though he lives in Agra. — Incorrect. The option says “has been never”. A word like “never” comes after the helping verb and before the main verb.
Corrected: Kabir has never been to the Taj Mahal, though he lives in Agra.

Option 4: The new teacher said that she had planned special something for Children’s Day. — Incorrect. The option says “special something”. With words like “something”, the adjective comes after the word.
Corrected: The new teacher said that she had planned something special for Children’s Day.