Which one of the following is the highest altitude zoo in the world?

Which one of the following is the highest altitude zoo in the world?

Cheyenne Mountain Zoo
Pandit G. B. Pant High Altitude Zoo
Himalayan Zoological Park, Gangtok
Padmaja Naidu Himalayan Zoological Park
This question was previously asked in
UPSC CDS-2 – 2016
The correct answer is Padmaja Naidu Himalayan Zoological Park.
The Padmaja Naidu Himalayan Zoological Park in Darjeeling, West Bengal, India, is recognized as the highest altitude zoo in India and among the highest in the world. Situated at an average altitude of 2,134 metres (7,000 feet), it specializes in the conservation of Himalayan fauna.
Other high-altitude zoos include the Cheyenne Mountain Zoo in Colorado Springs, USA, and Pandit G. B. Pant High Altitude Zoo in Nainital, India. While these are also at significant altitudes, the Padmaja Naidu Himalayan Zoological Park is widely cited as having the highest altitude among well-known zoos focused on conservation and public exhibition.