My father insisted that every minute _____ made full use of _____ the work well. [ ]

A. be; to do

B. has been; doing

C. be; doing

D. has been; to do

已知双眼皮和单眼皮是一对相对性状，其中双眼皮是显性性状，用D表示，单眼皮是隐性性状，用d表示。有一对夫妇均为单眼皮，那么生出的基因组成为DD子女的几率是[ ]

A．100%    

B．50%    

C．25%    

D．0