に vs. が

[GenjiMain]

Does the phrase "Who do you want to meet the most?" translate only as 誰に一番会いたいですか, or can が replace the に? If the が can't replace the に, why?

Thanks in advance.

 

[Toritoribe]

誰 is the subject in 誰が一番会いたいですか, thus it means "Who does want to meet the most?". This is valid only when the one the person in question (= 誰) wants to meet is obvious from the context. (If not, the target indicated by に can't be omitted just like 誰が彼女に一番会いたいですか "Who does want to meet her the most?".)