A major tourist destination in Karnataka known for historical monuments :

Hampi
Mysuru
Coorg
Udupi

The correct answer is A) Hampi.

Hampi is a UNESCO World Heritage Site in Karnataka, India. It was the capital of the Vijayanagara Empire from 1336 to 1565. The city is known for its ruined temples, palaces, and other historical monuments.

Mysuru is a city in Karnataka, India. It is the third-largest city in the state and the cultural capital of Karnataka. The city is known for its palaces, temples, and gardens.

Coorg is a district in Karnataka, India. It is known for its coffee plantations, hills, and forests.

Udupi is a city in Karnataka, India. It is known for its temples, beaches, and seafood.

Hampi is the correct answer because it is a major tourist destination in Karnataka known for historical monuments. The other options are also tourist destinations, but they are not as well-known for historical monuments as Hampi.