Is it he or you________in charge of the job and supposed to complete it punctually?[    ]

A. who is      

B. that is  

C. who are  

D. whom are

胎膜的组成()
胎儿附属物()

A．羊膜、叶状绒毛膜、底蜕膜

B．初级绒毛、二级绒毛、三级绒毛

C．绒毛膜、羊膜

D．胎盘、胎膜、脐带、羊水

E．底蜕膜、包蜕膜、真蜕膜