单选题 She asked the worker how long ______ to build the house.
A. it had taken B. had it taken
C. would it take D. it was taken

【正确答案】 A
【答案解析】[解析] 根据题意，此处应为关系副词短语how long引导的一个宾语从句。在该从句中除了关系词要前置外，其他成分要采用正常句子语序，可见A为唯一正确答案。