Correct Answer - Option 4 : Friday.
Given: 23 January 2005 = Sunday
We know, 22 January 2005 would be Saturday.
(23 January (Sunday) - 1 day = Saturday)
Number of days from 22nd January to 1sr January = 21 days
Number of odd days in 21 days = (7 × 3) + 0 i.e. 0 odd day
So, day on 1st January 2005 = Saturday
Day on 31st December 2004 = Saturday - 1 day = Friday
Hence, Friday is correct answer.
