Nagarjuna Konda is an island in the Krishna River known for its:

Buddhist archaeological site
Bird Sanctuary
Waterfalls
Tiger Reserve

The correct answer is: a) Buddhist archaeological site.

Nagarjunakonda is an island in the Krishna River in Guntur district of Andhra Pradesh, India. It is known for its Buddhist archaeological site, which is a UNESCO World Heritage Site. The site was once a major Buddhist center, and it contains a number of stupas, temples, and monasteries. The site is also home to a number of inscriptions, which provide valuable information about the history of Buddhism in India.

The other options are incorrect because:

  • b) Bird Sanctuary: Nagarjunakonda is not a bird sanctuary.
  • c) Waterfalls: Nagarjunakonda does not have any waterfalls.
  • d) Tiger Reserve: Nagarjunakonda is not a tiger reserve.