There is no doubt our educational system leaves something to be desired．
A. what
B. whether
C. if
D. that
网友回答
A. what
B. whether
C. if
(答案→)D. that
解析：考查同位语从句：句意：毋庸置疑,我们的教育体系,留给了我们一些为之憧憬的东西.即 有不足之处!There is no doubt that…，毫无疑问…，that引导的是同位语，说明doubt的内容，如果是There is doubt后面用whether，选D。