Reef producing coral are called

a. mobile

b. hermatypic

c. limestone polyps

d. all of the above

Option B.

Hermatypic.

Explanation:

Corals are Marine invertebrates organisms that belong to phylum cnidaria. An example of coral species is coral polyp.

Coral polyp build reef by secreting layers of calcium carbonate below their bodies and they are called hermatypic or hard corals or Stony corals.

option a and d is the correct answer

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