| Q5 to Q7:
Although many lines of evidence indicate
that birds evolved from ground-dwelling
theropod dinosaurs, some scientists remain
Line unconvinced. They argue that theropods(主题：鸟是否由t恐龙进化而来)
(5) appeared too late to have given rise to birds,（反对者：最早的t化石比最早的鸟A化石晚）
noting that Archaeopteryx lithographica—the
oldest known bird—appears in the fossil
record about 150 million years ago, whereas
the fossil remains of various nonavian
(10) maniraptor theropods—the closest known
relatives of birds—date only to about 115
million years ago. But investigators have （但最近发现了和A同时代的t化石）
now uncovered bones that evidently belong
to nonavian maniraptors dating to the time of
(15) Archaeopteryx. In any case, failure to find
fossils of a predicted kind does not rule out
their existence in an undiscovered deposit. （因此，没发现一种化石不能证明其不存在
Skeptics also argue that the fused连着的 clavicles锁骨
(the “wishbone叉骨”) of birds differ from the （怀疑者又说鸟的锁骨连着t的分开）
(20) unfused clavicles of theropods. This
objection was reasonable when only early
theropod clavicles had been discovered,
but fossilized theropod clavicles that look （但那时早期的t
just like the wishbone of Archaeopteryx （现在发现了晚期t的化石锁骨也连着）
(25) have now been unearthed. Finally, some
scientists argue that the complex lungs of（最后，又有人说t的肺进化不成鸟的肺）
birds could not have evolved from theropod
lungs, an assertion that cannot be supported
or falsified at the moment, because no fossil （但是由于肺没有化石，所以无法证明
(30) lungs are preserved in the paleontological
record.
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Q5:
The primary purpose of the passage is to
A. compare the development of two hypotheses concerning the evolutionary origin of birds
B. suggest revisions to the standard theory of the evolutionary history of birds
C. evaluate the usefulness of fossil evidence in determining the evolutionary history of birds
D. challenge the theory that birds evolved from ground-dwelling theropod dinosaurs
E. respond to criticisms of the theory that birds evolved from ground-dwelling
theropod dinosaurs
Answer: E
C为什么不可以？全文的结构都是在说根据某化石的evidence，鸟不可能是恐龙t进化的,然后用新的化石发现来反驳；然后又说从化石看锁骨有什么conflict，然后又用化石来证明；最后说肺的问题化石没有办法提供证据。尤其是15－18行直接说没有发现化石并不表明实际不存在。所以我决定全文都是围绕化石来说的。应该选C | 
