Explanation:

- To find the day of the week for 25 December 2010, start with 31 December 2009, which was a Thursday.

- 2010 was not a leap year, so it had 365 days. This means there were 365 days from 1 January 2010 to 31 December 2010.

- 365 days is equivalent to 52 weeks and 1 day.

- Therefore, each specific date in 2010 is one day ahead compared to the corresponding date in 2009.

- Given that 31 December 2009 was a Thursday, 31 December 2010 would be a Friday.

- Therefore, 25 December 2010, being 6 days before 31 December, would fall on a Saturday.

Option: 3 - Saturday