问题
This exercise is ________ difficult ________. [ ]
A:so; that few of us can do
B: so; that few of us can do it
C: too; for anyone of us to do
D: too; for anyone of us to do it
B: so; that few of us can do it
C: too; for anyone of us to do
D: too; for anyone of us to do it
正确答案是：
