Question

the organisms that make up a reef are mostly
select one:
a. sponges
b. diatoms
c. corals

what are krill?

select one:
a. small mollusks
b. small anemones
c. small shrimp

Explanation:

1. Coral reefs are primarily built and composed of colonial coral polyps that secrete calcium carbonate skeletons, forming the reef structure.
2. Krill are small, shrimp-like crustaceans that are a key part of marine food webs.

Answer:

1. c. corals
2. c. small shrimp