Choose the grammatically correct sentence:

The correct answer is Option (3) → Nobody in our colony had ever seen such heavy hail in April.

One negative word is enough:

• “Nobody” already makes the sentence negative.
• So the rest of the sentence uses “ever”, not “never”. Two negative words in one clause are wrong.

Why the Other Options are Incorrect?

Option 1: My cousin visits every Sunday the gurudwara. — Incorrect. The option puts “every Sunday” between the verb “visits” and its object “the gurudwara”. The object comes right after the verb.
Corrected: My cousin visits the gurudwara every Sunday.

Option 2: Meghna ordered the same thali like her friend. — Incorrect. “The same” is followed by “as”, not “like”.
Corrected: Meghna ordered the same thali as her friend.

Option 4: So sweet the mangoes were that we finished the whole box in a day. — Incorrect. When a sentence starts with “So + adjective”, the verb comes before the subject: “So sweet were the mangoes”.
Corrected: So sweet were the mangoes that we finished the whole box in a day.