Answer : 3. "Jaisalmer"
Explanation :

1. Sevan grass grows widely in Jaisalmer district.

2. Found mainly in the dry areas of western Rajasthan in the country.

3. This grass can tolerate drought due to welldeveloped root-rhizomes system.

4. Due to which it grows easily in the sandy soil of areas with less rainfall.

5. Its fodder is digestive and nutritious for animals.