LSAT-26-2-22

22.   Shortly after the Persian Gulf War, investigators reported that the area, which had been subjected to hundreds of smoky oil fires and deliberate oil spills when regular oil production slowed down during the war, displayed less oil contamination than they had witnessed in prewar surveys of the same area. They also reported that the levels of polycyclic aromatic hydrocarbons (PAHs)—used as a marker of combustion products spewed from oil wells ignited during the war—were also relatively low, comparable to those recorded in the temperate oil producing areas of the Baltic Sea.

Which one of the following, if true, does most to resolve the apparent discrepancy in the information above?

(A) Oil contaminants have greater environmental effects in temperate regions than in desert regions.

(B) Oil contamination and PAH pollution dissipate more rapidly in temperate regions than in desert regions.

(C) Oil contamination and PAH pollution dissipate more rapidly in desert regions than in temperate regions.

(D) Peacetime oil production and transport in the Persian Gulf result in high levels of PAHs and massive oil dumping.（D）

(E) The Persian Gulf War ended before the oil fires and spills caused as much damage as originally expected.

不太明白题目的意思. 哪里有discrepancy啊? 请NN指点.

Main idea:  

The level of contamination and PAH in a specific region is lower after the war than before the war.  Why ?  ( it is commonly assumed that war causes greater natural contamination by destructing inevitablly more oil fields )

A , B, C,  the subjects of comparison are wrong. It is not a difference between two different areas but that of situations of two particular time periods (before and after war) in one specific region.

E, The time when the war ended informs us nothing about the different result.

D,  By presenting a situation in peacetime, only it renders the possible explanation that bridges the gap between the discrepency before and after war.  

It is same t   the contamination caused by massive oil dumping and transportation in peacetime > that caused by war.