SAT tests your ability to identify main and supporting points and also between them.
A. differentiates
B. differentiate
C. differentiating
D. to differentiate
网友回答
A. differentiates
B. differentiate
C. differentiating
(答案→)D. to differentiate
解析:考查非谓语动词,此处是省略结构,完整为……and also your ability to differentiate between them.