Wood smoke contains dangerous toxins that cause changes in human cells. Because wood smoke presents such a high health risk, legislation is needed to regulate the use of open-air fires and wood-burning stoves.
Which of the following, if true, provides the most support for the argument above?
答案是E . In valleys where wood is used as the primary heating fuel, the concentration of smoke results in poor air quality.
不太明白B的解释
B. Within the jurisdiction covered by the proposed legislation, most heating and cooking is done with oil or natual gas.
——This point suggests that wood smoke presents few dangers to people in the area, and so decreases the need for legislation.
这里，加热和烹饪都是用油或天然气，与证明wood smoke对该地区人们无害，有何关系呢？
3X~ | 
