It’s kind you us with so much work.A. of; to help B. for; help C. of; helping

问题补充：

It’s kind you us with so much work.

A. of; to help B. for; help C. of; helping

答案：

解析：句意：帮我们做这么多工作你真太好了。It is +adj.+of/for sb. to do sth. 对某人来说做某事... 句型中形容词是kind，介词用of 。故选A。