Some workers in the nuclear power station were exposed to high levels of ______.
 
【正确答案】 A
【答案解析】 名词词义辨析。radiation“辐射,放射线,放射物”;cancer“癌症”;microwaves“微波”;high temperature“高温”。根据句中the nuclear power station提供的语境,只有radiation符合句意。故答案为A。