The correct option is C All but you loved me for money.
We use but as an alternative to except (for), apart from and bar to introduce the only thing or person that the main part of the sentence does not include. It is often used after words such as everyone, nobody, anything, anywhere, all, no, none, any, every.
But is used as a preposition when we put a noun or pronoun after it.
Option C is correct. It means that all except you loved me for money. The noun phrase 'you loved me for money', which also acts the object the preposition 'but', follows it.
Option A is incorrect because the sentence construction is flawed.
Option B is incorrect because the sentence is incomplete.
Option D is incorrect because 'but' has been used as a conjunction.