Answer : 4. "सवाई माधोपुर, भरतपुर और टोंक"
Explanation :

1. Maximum production of 'Khas' is from Sawai Madhopur, Bharatpur and Tonk belt of Rajasthan.

2. Khus is an aromatic grass from whose roots oil is extracted. This oil is used in perfumes, cosmetics, and medicinal products.

3. Rajasthan is a major producer of poppy oil.