Human facial expressions differ from those of animals in the degree they can be controlled on purpose.
A. with which
B. to which
C. of which
D. for which
网友回答
A. with which
(答案→)B. to which
C. of which
D. for which
解析：考查定语从句。在某种程度上，用to a degree或to some degree，因此当degree作先词时，关系代词用which或that。本题因介词提前紧跟关系词，故用to which形式，答案选择B.