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

Introduction / Context:
High-altitude zoos have special significance because they house species adapted to cold, mountainous environments and offer unique conservation opportunities. This question asks which zoo is considered the highest altitude zoo in the world, a fact that often appears in Indian and international general knowledge materials.

Given Data / Assumptions:

• Options include Cheyenne Mountain Zoo, Pandit G. B. Pant High Altitude Zoo, Himalayan Zoological Park (Gangtok) and Padmaja Naidu Himalayan Zoological Park.
• The question is about altitude (height above sea level), not area or animal count.
• We assume commonly cited figures about the elevation of these zoos.

Concept / Approach:
Padmaja Naidu Himalayan Zoological Park in Darjeeling, India, is widely reported as being at a very high altitude and is often described in GK texts as one of the highest, or the highest, altitude zoos. While Cheyenne Mountain Zoo and other Indian high-altitude zoos are also elevated, the GK convention frequently credits Padmaja Naidu Himalayan Zoological Park with this distinction. The approach is to recall this association and confirm it against the options.

Step-by-Step Solution:
Step 1: Identify which of the listed zoos are located in mountainous regions: Pandit G. B. Pant High Altitude Zoo (Nainital), Himalayan Zoological Park (Gangtok) and Padmaja Naidu Himalayan Zoological Park (Darjeeling). Step 2: Recognise that Padmaja Naidu Himalayan Zoological Park is situated at a high elevation in the Eastern Himalayas near Darjeeling. Step 3: Compare this with Cheyenne Mountain Zoo in the USA, which is also at high altitude but is not typically cited as the absolute highest in GK materials. Step 4: Remember that many Indian GK sources explicitly tag Padmaja Naidu Himalayan Zoological Park as the highest altitude zoo in the world. Step 5: Therefore, select Padmaja Naidu Himalayan Zoological Park as the correct option.

Verification / Alternative check:
If we look at descriptive information, Padmaja Naidu Himalayan Zoological Park is located at an elevation of more than 2,000 metres above sea level. Other high-altitude zoos like Nainital's Pandit G. B. Pant zoo and Gangtok's Himalayan Zoological Park are also elevated but are generally described as high-altitude Indian zoos rather than holding a world record. Cheyenne Mountain Zoo in Colorado is at a considerable elevation too, yet many GK compilations still cite the Darjeeling zoo as the highest. This supports Padmaja Naidu Himalayan Zoological Park as the expected answer.

Why Other Options Are Wrong:
Cheyenne Mountain Zoo: At a high elevation in Colorado, but not commonly cited in GK texts as the highest altitude zoo in the world.
Pandit G. B. Pant High Altitude Zoo: A high-altitude zoo in Nainital, India, but generally regarded as one of the highest in India rather than the world record holder.
Himalayan Zoological Park, Gangtok: Also situated in the Himalayas, yet not as widely publicised as holding the global altitude record.

Common Pitfalls:
Students may assume that the phrase “high altitude zoo” applies only to one Indian zoo and pick Nainital or Gangtok without recalling that Darjeeling's Padmaja Naidu Himalayan Zoological Park is more frequently associated with the global superlative. Another error is to overlook non-Indian options like Cheyenne Mountain Zoo. A careful reading of current GK references helps clarify that Padmaja Naidu Himalayan Zoological Park is the expected answer.

Final Answer:
Thus, the highest altitude zoo in the world, as commonly cited in GK materials, is the Padmaja Naidu Himalayan Zoological Park.