Question

the most prevalent environmental threat to human populations caused by landfills is
a. the attraction of vermin
b. the emission of poisonous chemicals into the atmosphere
c. the spread of radioactive waste
d. the contamination of surface and groundwater

Explanation:

垃圾填埋场中有害物质渗滤，最普遍的是污染地表水和地下水威胁人类。A选项吸引害虫并非最主要威胁；B选项排放有毒化学物质到大气不是最普遍的；C选项垃圾填埋场一般不存在放射性废物扩散问题。

Answer:

D. the contamination of surface and groundwater