The correct option is (a).
Explanation
The maritime boundary separating the Indian mainland from the island nation of Sri Lanka consists of specific shallow water bodies located off the southeastern coast of the Indian peninsula.Statement 1 is Correct: The Palk Strait is a strait located between the Tamil Nadu state of India and the Jaffna District of the Northern Province of Sri Lanka. It connects the Bay of Bengal in the northeast with Palk Bay in the southwest.
Statement 2 is Correct: The Gulf of Mannar is a large shallow bay forming part of the Laccadive Sea in the Indian Ocean. It lies between the southeastern tip of India (Rameswaram) and the west coast of Sri Lanka.
Statement 3 is Incorrect: The Gulf of Khambhat is an inlet of the Arabian Sea along the western coast of India, in the state of Gujarat. It separates the Kathiawar Peninsula from the southeastern part of Gujarat.
Statement 4 is Incorrect: The 10 Degree Channel is a wide channel in the Bay of Bengal that separates the Andaman Islands (specifically Little Andaman) from the Nicobar Islands (specifically Car Nicobar).
Key Takeaway: Sri Lanka is separated from India by a narrow channel of sea formed by the Palk Strait and the Gulf of Mannar.