Many corals secrete what to form a coral reef?
Options:
- (A) Chlorophyll
- (B) salt and water.
- (C) The area was once underwater
- (D) Chemical energy
- (E) aqueous solution
- (F) Organic compounds
- (G) gastropod shells
- (H) hard outer covering OK. Let's think hard:
Many corals secrete an exoskeleton that builds up to become a coral reef. An insect has a hard outer covering called an exoskeleton. Many corals secrete a hard outer covering that builds up to become a coral reef.
So, the final answer is (H).