To answer this question, we need to understand the history of Tamil being declared as a classical language.
Option A) 1985 - This option is incorrect because Tamil was not declared as a classical language in 1985.
Option B) 2004 - This option is correct because Tamil was declared as a classical language in 2004. The Government of India officially recognized Tamil as a classical language on 17th September 2004.
Option C) 2009 - This option is incorrect because Tamil was declared as a classical language in 2004, not 2009.
Option D) 2000 - This option is incorrect because Tamil was declared as a classical language in 2004, not 2000.
The correct answer is Option B) 2004. Tamil was declared as a classical language in 2004 by the Government of India.