An atoll is a reef or island indicative of an undersea volcano.

a. True

b. False

Hello!

The statement "An atoll is a reef or island indicative of an undersea volcano is True.

An atoll is a ring-shaped coralline oceanic island or a set of small islands from a coral reef that forms an internal lagoon. When there is a volcanic island, the Coral reef grows around it and the old volcano slowly sinks into the ocean, when the right conditions are met. The most famous atolls are the Bikini, Maldives, and Midway atolls.

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