Which of the following is NOT true of glial cells?

A)They form the myelin for axons.
B)They are outnumbered 10 to 1 by neurons in the nervous system.
C)They deliver fuel molecules to neurons and remove the waste products of metabolism.
D)They are important for the growth and development of the nervous system.
E)They regulate the composition of the extracellular fluid in the CNS.