I think you want to ask something like "lequel est correct?" "Ce qui" is used to translate "which" in sentences like: "He is very hard-working, which helps him to learn quickly". In this example, "which" is like a shorthand for "the fact that he is very hard-working", and grammatically "which" is the subject of "which helps him to learn quickly".

A mon avis... ou: Selon moi...