选取萃取剂时,一般从能否与金属离子形成螯合物、萃取剂亲水基团、疏水基团及空间结构等因素来考虑。试判断下列萃取剂中可能对金属离子萃取效率最高的是

A、[img=~/QImg/2013-10-14-10-14-34/image022.jpg]
B、CH[img=~/QImg/2013-10-14-10-14-34/image003.jpg]CH[img=~/QImg/2013-10-14-10-14-34/image001.jpg]OH
C、CH[img=~/QImg/2013-10-14-10-14-34/image003.jpg]CH[img=~/QImg/2013-10-14-10-14-34/image001.jpg]OCH[img=~/QImg/2013-10-14-10-14-34/image001.jpg]CH[img=~/QImg/2013-10-14-10-14-34/image003.jpg]
D、CH[img=~/QImg/2013-10-14-10-14-34/image003.jpg](CH[img=~/QImg/2013-10-14-10-14-34/image001.jpg])[img=~/QImg/2013-10-14-10-14-34/image003.jpg]OH