Correct Option
The correct option is (a).
Explanation
Lakes are classified based on their mode of formation. Natural lakes result from geological, glacial, tectonic, or fluvial processes, whereas artificial lakes are man-made reservoirs created by damming streams for purposes such as irrigation, water supply, or recreation.
- Kodaikanal Lake (Tamil Nadu): This is an artificial lake. It was created in 1863 by Sir Vere Henry Levinge, the then Collector of Madurai, by damming three streams flowing through the valley in the Palani Hills.
- Kolleru Lake (Andhra Pradesh): This is a natural freshwater lake located between the deltas of the Godavari and Krishna rivers. It serves as a natural flood-balancing reservoir for these two rivers.
- Nainital Lake (Uttarakhand): This is a natural freshwater lake of tectonic origin, situated in the Kumaon foothills of the outer Himalayas.
- Renuka Lake (Himachal Pradesh): This is a natural lake and the largest in Himachal Pradesh. It is a designated Ramsar wetland site formed due to geological shifts.
Key Takeaway: Kodaikanal Lake is a man-made structure developed during the British colonial period, whereas Kolleru, Nainital, and Renuka are natural geological formations.