单选题 -How did you pay，the workers?
-As a rule，they were paid by ______．
[A] the hour [B] an hour [C] hour [D] hours

【正确答案】 A
【答案解析】[考点] 冠词的用法
[解析] 本句意为：一你怎样给工人们付钱?一按照规定，按小时给他们付钱。表示“按小时(计算等)”，单位名词前有定冠词the。