Which of the following is associated with Atoll?

PYQ SSC JE (Junior Engineer) 2023

1. A.

   Ocean basins with gently sloping terrain

2. B.

   It is made up of two mountain chains separated by a large depression

3. C.

   It is a seamount with a flat top

4. D.

   Low islands found in the tropical oceans consisting of coral reefs

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