【单选题】

1Coral reefs are one of the earth’s most ancient ecosystems and also the richest, most diverse, and most beautiful ecosystems in any ocean. The huge cities built by corals provide shelter and food for billions of other marine animals.

A、quarter of all sea creatures depend on coral reefs during some part of their life cycles.
2 In the past century, the ocean’s surface temperature has risen an average of 1.8 degrees Fahrenheit. It has taken only this slight increase in sea-surface temperature to sicken the world’s coral reefs. The brilliant blue, purple, green, gold, and pink have begun to disappear as a disease called bleaching drains the color and the life from the reefs. Scientists have reported mass bleaching on reefs in theCaribbean, in southern Japan, in Indonesia, and on the world’s largest coral reef, the GreatBarrier Reef, where the corals have bleached to a dirty white.
3Bleaching has killed more corals than all other causes combineD、More than 16 percent of the world’s corals have sickened and died from bleaching. Millions of aquatic animals that depend directly or indirectly on corals have died as well--anemones, sponges, mollusks, shrimp, crabs, fish, turtles, and seabirds--making the loss of corals a catastrophe for the natural worlD、
All of the following are effects of the bleaching of coral reefsEXCEPT
A、fading colors
B．loss of dependent animals
C．death of corals
D．rising water level