Answer the following question given this paragraph: In which of the following regions would you expect to find photosynthetic organisms? a. The aphotic zone, the neritic zone, the oceanic zone, and the benthic realm. The photic zone, the intertidal zone, the neritic zone, and the oceanic zone. The photic zone, the abyssal zone, the neritic zone, and the oceanic zone. The pelagic realm, the aphotic zone, the neritic zone, and the oceanic zone. Coral Reefs Coral reefs are ocean ridges formed by marine invertebrates living in warm shallow waters within the photic zone of the ocean. They are found within 30 north and south of the equator. The Great Barrier Reef is a well-known reef system located several miles off the northeastern coast of Australia. Other coral reefs are fringing islands, which are directly adjacent to land, or atolls, which are circular reefs surrounding a former island that is now underwater. The coral-forming colonies of organisms (members of phylum Cnidaria) secrete a calcium carbonate skeleton. These calcium-rich skeletons slowly accumulate, thus forming the underwater reef (Figure 20.29). Corals found in shallower waters (at a depth of approximately 60 m or about 200 ft) have a mutualistic relationship with photosynthetic unicellular protists. The relationship provides corals with the majority of the nutrition and the energy they require. The waters in which these corals live are nutritionally poor and, without this mutualism, it would not be possible for large corals to grow because there are few planktonic organisms for them to feed on. Some corals living in deeper and colder water do not have a mutualistic relationship with protists; these corals must obtain their energy exclusively by feeding on plankton using stinging cells on their tentacles. Q: Ocean ridges formed by marine invertebrates living in warm shallow waters within the photic zone of the ocean are called what? A:

Select from the following. A). lagoon; B). trenches; C). break water; D). coral reefs;
Answer:
D).