Explanation:

Largest Coral Reef of the world is in Australia named the Great Barrier Reef composed of over 2900 individual reefs and 900 islands.

The Great Barrier Reef is the world's largest coral reef system composed of over 2,900 individual reefs and 900 islands stretching for over 2,300 kilometres over an area of approximately 344,400 square kilometres. The reef is located in the Coral Sea, off the coast of Queensland, Australia.