Final answer:
The myelin lipid, produced by Schwann cells in the PNS and oligodendrocytes in the CNS, functions as insulation for nerve fibers, facilitating the fast transmission of electrical signals. The correct answer is a) Insulation of nerve fibers.
Step-by-step explanation:
Schwann cells and oligodendrocytes manufacture a lipid called myelin. The function of this lipid can best be described as providing insulation for nerve fibers, hence the correct answer is a) Insulation of nerve fibers.
Myelin is a lipid-rich sheath that surrounds the axon, creating a myelin sheath that is integral for the fast and efficient transmission of electrical signals along the axon in the nervous system.