Correct Answer - Option 1 : 25 Minutes

A clock gains 2 minutes every hour.

This means, every 60 minutes, clock gains 2 minutes.

Thus, every minute, clock gains 1/30 minutes.

From 3:30 pm to 4:00 a.m., we have 12 hours and 30 minutes.

In twelve hours, the clock gains 12 × 2 minutes i.e. 24 minutes.

In 30 minutes, the clock gains 1/30 × 30 minutes i.e. 1 minute.

Thus, total minutes gained in 12 hours and 30 minutes is 24 + 1 i.e. 25 minutes.

Hence, **25 Minutes **is correct.