問題詳情

(37~40)     Coral bleaches when the water it’s in is too warm for too long._(37)_. Without the colourful algae, the coral flesh becomestransparent, revealing the stark white skeleton beneath.    And because the algae provides the coral with 90% of its energy,it begins to starve. Unless _(38)_, the coral dies and gets taken over by a blanket of seaweed. Once that happens it can take a decade for the coral to recover – and even then that recovery depends on the reef not being hit by other stressors such as water pollution.   The thick seaweed is a sign of extreme ecosystem meltdown.Fish can no longer use the coral structure as shelter – blocked by the plants – and before long _(39)_, leaving little chance of full recovery within the next 10 years.   When the coral dies, the entire ecosystem around it transforms.Fish that feed on the coral, use it as shelter, or nibble on the algae that grows among it die or move away. _(40)_ too. But the cascadingeffects don’t stop there. Birds that eat fish lose their energy source,and island plants that thrive on bird droppings can be depleted. And,of course, people who rely on reefs for food, income or shelter from waves –some half a billion people worldwide –lose their vital resource.
(A)the temperatures quickly return to normal
(B) the bigger fish that feed on those fish disappear
(C) the coral polyps gets stressed and spit out the algae thatlive in inside them
(D) the coral structures themselves are likely to collapse
37

參考答案

答案：C
難度：適中0.5
統計：A(0),B(0),C(0),D(0),E(0)

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