Explanation:

- The first census of the 21st century in India was conducted in 2001.

- Option 2: 2011 is when the second census of the 21st century was conducted in India. This is the correct answer.

- Option 1: 2014 is incorrect. No census was held in this year.

- Option 3: 2004 is incorrect. It's not a census year.

- Option 4: 2009 is also incorrect. This year didn't see a census activity.

The census is a decennial activity in India, meaning it happens every ten years. The 2011 census was the 15th National Census since 1871.