Mr. Wang has taught in our school he came to Hainan.A. when B. for C. since

问题补充：

Mr. Wang has taught in our school he came to Hainan.

A. when B. for C. since

答案：

解析：句意：王先生自从来到海南就在我们学校教书了。when当……时候；for因为，连接并列句；since自从，从句用过去时，主句用现在完成时。如：The Smiths have lived in China since he moved here史密斯一家人自从来到这里就住在中国。故选C。