We are hereby to introduce you one new manicure set which is the result（）numerous R & D (research and development) resou

We are hereby to introduce you one new manicure set which is the result（）numerous R & D (research and development) resources in our company.

正确答案：of

解析:本题考查介词 of 的用法。全句意思是：特此我们想向您推介一款我们公司花了大量研究投入的新型美容套装工具。