单选题 All flights ______ because of the storm, they decided to take the train.
A. having canceled B. having been canceled
C. were canceled D. have been canceled

【正确答案】 B

【答案解析】[解析] 句子的大意为：所有航班都因为风暴取消了，所以他们决定乘火车。此句为独立主格结构，相当于with all fights having been cancelled，fights和cancel之间关系为被动，排除A、C，如果答案为D，句中的标点应为句号。所以B项符合题意。