If 29 July 2001 is Sunday, then what will be the day of the week on 20 February 2015?

Correct option is B

Logic:
29 July 2001 is Sunday.
From 29 July 2001 to 29 July 2014, there are 16 odd days.
(10 odd days of 10 normal years, and 6 odd days of 3 leap years.)
Odd days = Remainder of (16 ÷ 7) = 2
Now, add the odd days to the given day of week:
Sunday + 2 = Tuesday (Monday, Tuesday)
So, 29 July 2014 was Tuesday.
So, now, the number of odd days from 29 July 2014 to 20 February 2015 = 3
Thus, 20 February 2015 → Tuesday + 3 = Friday.