由 Huang Hsin-Yi » 2008-03-11 20:46
GWD-3-Q7:
The passage suggests that the fact that ALH84001 has been on earth for 13,000 years has been used by some scientists to support which of the following claims about ALH84001?
A. ALH84001 may not have originated on Mars.
B. ALH84001 contains PAH’s that are the result of nonbiological processes.
C. ALH84001 may not have contained PAH’s when it landed on Earth.
D. The organic molecules found in ALH84001 are not PAH’s.
E. The organic molecules found in ALH84001 could not be the result of terrestrial contamination.
請問B為何不行?
Yet McKay’s team notes that the
particular combination of PAH’s
in ALH84001 is more similar to the
combinations produced by decaying
organisms than to those originating
form nonbiological processes.
而正確選項C,我一直想不通,如何推出答案
這段文章要如何推出
For example,
ALH84001 has been on earth for
13,000 years, suggesting to some
scientists that its PAH’s might have
(25) resulted form terrestrial contamination
我知道了,因為ALH84001 來自火星,而PAH是受到地表污染的話,表示ALH掉落到地球時,沒包含PAH
不過B似乎解釋另一種推測,該如何排除?