Final answer:
An environment with a lagoon featuring abundant calcite-shelled animals is characteristic of a Coral Reef, which is known for high biodiversity and is typically located in shallow, warm ocean waters. The correct option is C.
Step-by-step explanation:
An environment characterized by a lagoon with abundant calcite-shelled animals is likely to be a Coral Reef.
Coral reefs are formed by the calcium carbonate skeletons of coral organisms, which are marine invertebrates in the phylum Cnidaria.
These ecosystems are usually found in shallow, warm ocean waters and have a symbiotic relationship with algae, which live in their tissues.
Coral reefs have a high biodiversity and are often found in tropical regions, offering protection and a habitat for a variety of marine life, including calcite-shelled animals such as mollusks and foraminifera. The correct option is C.