When first to

【题目】When first to ___________ the market, the products enjoyed great success. (   )

A.introducing B.introduced

C.introduce D.being introduced

【答案】C

【解析】

本题考查动词不定式的用法。根据When first to              the market，the products enjoyed great success. 可知当首次引入市场时，这些产品获得了巨大的成功。first to do sth表示第一次做某事。故选C。