Beijing is a beautiful city. I fell in love it when I came here.A. at B. with C. as

问题补充：

Beijing is a beautiful city. I fell in love it when I came here.

A. at B. with C. as

答案：

解析：句意：北京是一个美丽的城市。我来到这里的时候就爱上了它。Fall in love with爱上，是一个固定短语。所以选B。