The following text is from an article about coral reefs.
Coral reefs are often called the "rainforests of the sea" because of their incredible biodiversity. These underwater ecosystems cover less than 1% of the ocean floor yet support approximately 25% of all marine species. Fish, mollusks, crustaceans, and countless other organisms depend on reefs for food, shelter, and breeding grounds.
What is the main purpose of the text?
To warn readers about the dangers facing coral reefs
To compare coral reefs to terrestrial rainforests in detail
To highlight the ecological importance of coral reefs
To explain how coral reefs are formed over time
Correct Answer: C
Choice C is the best answer. The text emphasizes coral reefs' biodiversity (supporting 25% of marine species) and their role as habitat for many organisms—highlighting their ecological importance.
- Evidence: The text mentions "incredible biodiversity," "support approximately 25% of all marine species," and provide "food, shelter, and breeding grounds."
- Reasoning: All these details illustrate how vital reefs are to the ocean ecosystem.
- Conclusion: The purpose is to highlight this importance.
đź’ˇ Strategy: Synthesize the details (biodiversity, habitat support) to find the common theme (importance).
Choice A is incorrect because no threats or dangers are mentioned. Choice B is incorrect because the comparison is brief, not detailed. Choice D is incorrect because reef formation is not discussed.