【题目】It's reported that 70% of people in China are _________ about the food security situation after so many accidents.
A.concerning
B.concerned
C.cautious
D.certain

【答案】B
【解析】考查固定短语。句意：据报道，发生这么多事故之后，中国有7０％的人担忧食物安全。be corncerned about固定短语，“对.....担忧”。可知答案为B。