Explanation:

- The world's highest ground-based telescopic observatory is located in India.

- It's the Indian Astronomical Observatory at Hanle, in the Ladakh region.

- At around 4,500 meters, it offers clear skies, perfect for astronomical research.

- Option 1: Colombia - Known for its biodiversity, but not for having the highest observatory.

- Option 3: Nepal - Hosts many high-altitude locations, yet lacks the world's highest observatory.

- Option 4: Switzerland - Renowned for its mountains, but its observatories are not at the highest globally.

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