Which of the following cells manufacture P0?

Protein zero (P0) is the predominant protein in myelin in the peripheral nervous system and its function is to stabilize adjacent plasma membranes by interaction with similar P0 molecules. Which of the following cells manufacture P0?
(A) fibrous astrocytes
(B) microglia
© oligodendrocytes
(D) protoplasmic astrocytes
(E) Schwann cells