Explanation:

- Option 1: 2000

- This year is not correct for the launch of the National Food for Work Programme. This year saw India grappling with various economic and political changes, but no significant launch of such a program.

- Option 2: 1991

- This year was primarily notable for the economic liberalization in India. The focus was on privatization and deregulation, not launching a food-for-work scheme.

- Option 3: 2002

- While there were initiatives to support rural development during this period, it was not the year when the National Food for Work Programme was launched.

- Option 4: 2004

- Correct Answer: The National Food for Work Programme was launched in 2004. Aimed at providing supplementary wage employment and food security, this program targeted India's backward districts.

The correct answer is Option 4: 2004.