Coral reefs occupy less than 1 percent of the ocean floor but support an estimated 25 percent of marine species. Reef-building corals depend on symbiotic algae living inside their tissues; when water temperatures rise above the corals' tolerance range, the algae are expelled in a process called bleaching. Without their algae, corals lose their primary food source and color, and prolonged bleaching events often kill entire reef systems.
Which conclusion most logically follows from the passage?
- A
Bleaching events strengthen reefs by removing competing algae
- B
Coral reefs occupy a disproportionately small share of marine biodiversity
- C
Marine species can readily relocate from damaged reefs to similar habitats
- Dcheck_circle
The vulnerability of coral reefs to warming has implications extending well beyond reef-building corals themselves
Explanation
25% of species depending on 1% of seafloor means reef damage affects far more than corals, supporting B. A reverses the proportion; C contradicts the lethal effect; D is unsupported.