Which sentence from the section helps explain that humans are one cause of coral bleaching?AReefs could disappear entirely by the end of the century.BClarke says coral bleaching is a clear sign of climate change.CCoral bleaching may seem grim.DBut reefs can improve if humans take action.

Which sentence BEST summarizes the section "Coral And Bleaching"?ANOAA takes care of coral reefs.BCoral reefs with algae have bright colors.CCoral bleaching is a sign that coral are unhealthy.DCoral, also called polyps, are marine invertebrates.

It affects the health of living things in the oceans, as well as people's livelihoods and food security.How does this sentence support the MAIN idea of the article?AIt shows which types of coral are bleaching.BIt shows how to slow down coral bleaching.CIt shows why coral bleaching is a big problem.DIt shows who is helping to stop coral bleaching.

Explain why the death of corals is especially threatening to a reef ecosystem, even if it has high biodiversity.

While coral reefs only make up a small portion of the ocean geographically, they are home to about a quarter of all ocean organisms. Coral reefs are an integral part of ocean ecosystems, but ecologists are concerned about climate change interfering with coral's food chains. The ecologists say that by eliminating overfishing and human pollution, reefs will have higher survival rates and become significantly more healthy. According to the text, why are ecologists worried about coral reefs? They can be toxic for specific types of marine wildlife.eliminateThey are not big enough to home all of the species who need to live there. eliminateThey are being overfished so their populations are dwindling.eliminateThey are unable to sustain life due to the severe impacts from various human activities.

Which sentence from the article helps the reader understand that coral reefs are important?AMonths of increasing ocean temperatures are damaging reefs.BThis leaves the coral reefs exposed to disease.CAustralia's Great Barrier Reef is the largest coral reef system in the world.DRoughly 850 million people worldwide rely on coral reefs.