Explanation:

- The Kudankulam Nuclear Power Plant is situated in the state of Tamil Nadu, India.

- It is a significant collaboration between India and Russia in the field of nuclear energy.

- The first unit was officially dedicated to the nation in August 2016 by Indian PM Narendra Modi and Russian President Vladimir Putin.

- Tamil Nadu is located in the southern part of India, known for its diverse geography and industrial economy.

- Option 1: Maharashtra

- Located on the west coast of India.

- Known for cities like Mumbai and Pune.

- Option 2: Tamil Nadu

- The correct option.

- Kudankulam is situated in this state.

- Option 3: Karnataka

- Situated to the north of Tamil Nadu.

- Known for its tech hub, Bengaluru.

- Option 4: Andhra Pradesh

- Lies to the north of Tamil Nadu along the coast.

- Known for cities like Visakhapatnam and Amaravati.

- Option 5: Kerala

- Southwest state adjacent to Tamil Nadu.

- Famed for its backwaters and natural beauty.