My parents used ________ they had to get a new car for me.

A．which

B．that

C．what

D．all what

采用原位轴压法、扁顶法、切制抗压试件法检测砌体时，当选择6个测区却有困难时，可选取不少于（）个测区测试，但宜结合其他非破坏检测方法综合进行强度推定。

A.5

B.4

C.3

D.2