The clever boy made a hole in the wall, _____ he could see _____ was going on inside the house. [ ]

A. which; what

B. through which; what

C. through that; what

D. what; that

胎头衔接是指()

A．枕骨进入骨盆入口平面

B．顶骨进入骨盆入口平面

C．双顶径进入骨盆入口平面达到或接近坐骨棘平面

D．双顶径到达坐骨棘平面

E．双顶径到达坐骨结节平面