If it is 12 noon in New Delhi, what will be the time in London, UK ?

The time difference between India and the United Kingdom is determined by the longitudinal positions of the two regions relative to the Prime Meridian.

• Indian Standard Time (IST): India's time is based on 82.5° E longitude, which is 5 hours and 30 minutes ahead of Greenwich Mean Time (GMT).
• Greenwich Mean Time (GMT): London is situated on the Prime Meridian (0° longitude), which serves as the reference for UTC.

To calculate the time in London when it is 12:00 Noon in New Delhi, you must subtract the 5.5-hour difference from the Indian time:

12:00 PM (Noon) - 5 hours 30 minutes = 6:30 A.M.

Since India is ahead of the UK, the time in London will be earlier in the day. Thus, Option A is the correct answer.