下列适于作单侧检验的时期是()。
A.已知A药优于B药
B.不知A药好还是B药好
C.已知A药不会优于B药
D.知A药与B药差不多好
E.以上都不对
参考答案:C
I _____ go shopping when the telephone rang.[ ]
A. was about to
B. was just to
C. had to
D. wanted to