Answer : 2. "Gulf of Mannar and Palk Strait"
Explanation :

Scientists from ISRO successfully mapped the submerged structure of Adam’s Bridge (Ram Setu), a 48 km limestone chain connecting Rameswaram Island (India) to Mannar Island (Sri Lanka). The bridge separates the Gulf of Mannar and Palk Strait, with shallow waters of 1-10 meters. Geological evidence indicates it was a former land connection, referenced in the Ramayana and Islamic legend, but submerged since 1480 due to natural calamities.