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突然发现题目看不懂了。。。晕。。。。 Which of the following, if true, would most clearly support the argument about keystone
status advanced in the last sentence of the passage (lines 15 – 19)? 这里的advance是什么意思? 是叫我们往15-19行前面看吗?可答案就在15-19行啊 可以翻译一下下题吗?。。。。。。。
虽然应该不需要,不过还是附上完整版。。。
Which of the following, if true, would most clearly support the argument about keystone
status advanced in the last sentence of the passage (lines 15 – 19)?
A species of bat is primarily responsible for keeping insect populations within an
ecosystem low, and the size of the insect population in turn affects bird species
within that ecosystem.
B.A species of iguana occupies a keystone role on certain tropical islands, but does
not play that role on adjacent tropical islands that are inhabited by a greater number
of animal species.
C.Close observation of a savannah ecosystem reveals that more species occupy
keystone roles within that ecosystem than biologists had previously believed.
D.As a keystone species of bee becomes more abundant, it has a larger effect on
the ecosystem it habits.
E.A species of mouse that occupies a keystone role in a prairie habitat develops
coloration patterns that camouflage it from potential predators.
Keystone status appears to depend on 15 context, whether of particular geography or of such factors as community diversity 16 (for example, a reduction in species diversity may thrust more of the remaining species 17 into keystone roles) and length of species interaction (since newly arrived species 18 in particular may dramatically affect ecosystem).
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