TPO 15 MASS EXTINCTIONS 最後一題 - 英檢

14.Answer Choices:
○1. Asteroid impacts, evolutionary developments, and changes in Earth' s
climate and in the positions of the continents have all been proposed as
possible causes of mass extinctions.
○2. Researchers have observed 26-million-year cycles in extinction rates of
a number of fossil groups that could all be attributed to the same cause.
○3. According to the Alvarez hypothesis, much of the iridium originally
present on Earth was thrown into the atmosphere as a result of an asteroid
impact that also caused a mass extinction.
○4. The unusual distribution of iridium on Earth and the presence of craters
and heat-shocked quartz are central to the theory that an asteroid impact caused
the late Cretaceous event.
○5. The collision between Earth and a large asteroid resulted in massive
damage and generated enough heat to cause irreversible changes in Earth's
atmosphere.
○6. There was a particularly large mass extinction that occurred around 250
million years ago at the end of the Permian period, whose cause could not be
determined.
正確答案是1,2,4
想問第二選項一直很困擾我
Researchers have observed 26-million-year cycles in extinction rates of
a number of fossil groups that could all be attributed to the same cause.

這邊講到the same cause 該段也沒說倒是發生於同一原因
這個同一個原因是第四段後面討論的a companion star?
謝謝回復

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