What are two kinds of solid structures made by marine animals from minerals they extract from seawater?

shells and coral reefs

Explanation:

The two types of solid structures made by marine animals from minerals that they extract from seawater are shells and coral reefs.

Shells are hard, calcareous organs present on the outside of the shellfish's body. As mollusks do not have bones inside the body, the shells have the function of ensuring the protection of the body of these animals.

Coral reefs are formations constructed from the deposition of calcium carbonate by various marine organisms, mainly corals, but other organisms such as calcareous algae and molluscs also contribute to the formation of reef substrates. Corals are small and very fragile Anthozoa class cnidarian animals that use calcium carbonate from the water to build a hard exoskeleton.

answer; i believe its (ovulation);