Explanation:

- Khadi Gramodyog Vikas Yojana focuses on promoting village industries.

- The scheme provides common facilities, modern technology, and training to boost rural entrepreneurship.

- Option 1: 21-60 years - This option suggests a broad range covering a significant working population.

- Option 2: 16-30 years - Targets a younger, potentially more adaptive demographic.

- Option 3: 20-35 years - Focuses on young adults, a prime age for entrepreneurship.

- Option 4: 18-55 years - Encompasses a wide range of working-age individuals, tapping into both youth and experience.

- Option 5: 25-40 years - Concentrates on those likely to have work experience and stability.

The correct target age group for Khadi Gramodyog Vikas Yojana is Option 4: 18-55 years.