Question

Cristae are the inner folded membrane of the mitochon drion

Answer 1

That is true. Cristae are the foldings of the inner membrane of the mitochondria.

Answer 2

A crista is a fold in the inner membrane of a mitochondrion. The name is from the Latin for crest or plume, and it gives the inner membrane its characteristic wrinkled shape, providing a large amount of surface area for chemical reactions to occur on.