Whom would you rather___ with your sister

陈述句是: You would rather have (sb.) go with your sister.这样看清楚点。

have sb. do的意思是让某人做某事
have sb. done 使某人遭遇... / 让某人承受...
have sth. done 意思是使某事完成
have sb. doing 的意思是让某人一直做某事

句意是：你愿意让谁陪你姐姐一起去。所以选C。

have sb. do sth
选C。

would have+动词原型为固定搭配

have sb do 让某人做某事！sb是宾格的！所以用whom提问！