The correct answer is glial cells.
The glial cells provide support and insulation between the neurons. The glial cells are the most profuse kind of cells in the central nervous system. The kinds of glial cells include astrocytes, oligodendrocytes, ependymal cells, microglia, Schwann cells, and satellite cells.
These cells help to sustain homeostasis, produce myelin and offer protection and support for the neurons.