Why does the author mention that reefs shelter about a quarter of marine species?
Coral reefs are built by tiny animals called polyps, which secrete a hard skeleton of calcium carbonate. Over many generations the skeletons of dead polyps accumulate and form the structure of the reef. Reef-building corals live in partnership with microscopic algae that live inside their tissues. The algae use sunlight to make food and share it with the coral, which is why reefs are found mostly in shallow, clear water where sunlight can penetrate. This partnership is sensitive to temperature: if the water becomes too warm, the corals expel their algae and turn white, a process called bleaching. Although bleached corals can recover if conditions improve, prolonged stress can kill them. Because reefs shelter about a quarter of all marine species, their loss would have effects far beyond the coral itself.
Answer and explanation
Correct answer: C. To show that the loss of reefs would affect many other animals
- Step 1: The sentence ends with effects beyond the coral. Step 2. The statistic supports the importance of reefs. Answer: to show the wider effect of losing reefs. Why not the others: these topics are not the purpose of the statement.
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More Academic Passages (Set 2) questions
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