Ms.Claire is a strict bu kind teacher ,( )l respect and appr

Ms.Claire is a strict but kind teacher ,( )l respect and appreciate most用one 的时候相当于the one who 也就是说后面就像是一个非限制性定语从句,the one who I respect and appreciate most.
在这个括号内还可以填：who,whom
再问： the one who =who吗为什么？