Which of the following is the largest lagoon lake situated on the east coast of India ?

The correct answer is B) Chilka. Chilka lagoon lies on the Odisha coast, spread across Puri, Ganjam and Khordha districts, and is the largest brackish water lagoon in India. Its area swells during the monsoon and shrinks in summer, so the figure is usually quoted as a range. It was declared a Ramsar site in 1981.

• A) Pulicat is India's second largest brackish water lagoon, shared by Andhra Pradesh and Tamil Nadu. It is smaller than Chilka.
• C) Kolleru is a freshwater lake, not a lagoon, lying between the Godavari and Krishna deltas in Andhra Pradesh. It is India's largest freshwater lake, so the lagoon-versus-lake distinction is the trap here.
• D) Kilivali is a much smaller coastal lagoon and does not compete for the top position.

The concept is the classification of coastal wetlands, which links to the Environment and Geography syllabus and to Mains questions on wetland conservation under the Wetlands (Conservation and Management) Rules, 2017.

Trap: aspirants mix up 'largest lake' with 'largest lagoon' and pick Kolleru, which is a freshwater lake.