Which one of the following is a lagoon?

1. A lagoon is a shallow body of water separated from a larger body of water (usually the sea) by barrier islands or reefs. 2. Let's examine the options: (A) Ashtamudi Lake in Kerala is a large estuarine system, often referred to as a backwater or lagoon. (B) Chilka Lake in Odisha is the largest coastal lagoon in India and the second largest brackish water lagoon in the world. (C) Periyar Lake in Kerala is an artificial lake formed by the construction of the Mullaperiyar Dam on the Periyar River. It is a reservoir, not a natural lagoon. (D) Pulicat Lake, located on the border of Andhra Pradesh and Tamil Nadu, is the second largest brackish water lagoon in India. 3. The question asks which one *is* a lagoon. Ashtamudi, Chilka, and Pulicat are all lagoons or lagoon-like systems. Periyar Lake is distinctly not a lagoon. Given the provided answer is C (Periyar Lake), the question might have been intended to ask 'Which one of the following is *NOT* a lagoon?'. Assuming the question is 'Which one...is a lagoon?' and the answer key points to C, there is a significant discrepancy. However, strictly following the answer key 'C' implies Periyar Lake is being identified as a lagoon, which is factually incorrect. If we assume the question meant 'Which is NOT a lagoon?', then C would be correct. *Analysis proceeds assuming the question meant 'Which is NOT a lagoon?' to align with the provided answer 'C'.*