Answer : 4. "Dehradun"
Explanation :

The Indian Forest Research Institute (IFRI) is located in Dehradun, Uttarakhand, India. Dehradun serves as the headquarters for IFRI, which is a premier institution dedicated to research and education in the field of forestry and forest management. The institute plays a vital role in conducting research, providing training, and disseminating information related to forestry and environmental conservation in India.