Even though they are not doubtful at all John will pass the exam, I still wonder he is fully prepared.
A. whether; that
B. that; whether
C. that; that
D. whether; whether
网友回答
A. whether; that
(答案→)B. that; whether
C. that; that
D. whether; whether
解析：考查同位语从句。boubtful“怀疑的，有疑问的”，用于肯定句时，同位语从句用whether引导；用于否定句时，同位语从句用that引导；wonder“怀疑，想知道”，用whether引导宾语从句。故选B。