The correct answer is: D. Kullu.
Shilli Conservation Reserve is a protected area in the Kullu district of Himachal Pradesh, India. It was established in 1988 to protect the habitat of the Himalayan tahr, a wild goat that is found in the Himalayas. The reserve is also home to a variety of other wildlife, including snow leopards, musk deer, and red pandas.
The reserve is located in the Kullu Valley, which is a popular tourist destination. The reserve is open to tourists, but there are restrictions on where they can go and what they can do. The reserve is managed by the Himachal Pradesh Forest Department.
Option A: Sirmaur is a district in Himachal Pradesh. It is located in the northern part of the state. The district is home to a variety of wildlife, including snow leopards, musk deer, and red pandas. However, Shilli Conservation Reserve is not located in Sirmaur district.
Option B: Solan is a district in Himachal Pradesh. It is located in the central part of the state. The district is home to a variety of wildlife, including snow leopards, musk deer, and red pandas. However, Shilli Conservation Reserve is not located in Solan district.
Option C: Kinnaur is a district in Himachal Pradesh. It is located in the eastern part of the state. The district is home to a variety of wildlife, including snow leopards, musk deer, and red pandas. However, Shilli Conservation Reserve is not located in Kinnaur district.