Astrocytes play several crucial roles in the central nervous system, but one of the options provided does not accurately describe their function. The correct answer is:
c provide the defense for the CNS
While astrocytes do support neurons and contribute to the overall health of the neural environment, the primary defense role in the central nervous system is carried out by microglia, which are responsible for immune responses. Astrocytes mainly help in supporting and nourishing neurons, regulating the chemical environment, and assisting in the repair and maintenance of the blood-brain barrier. They are not the main players in defense against pathogens or injury in the CNS, which is why option ‘c’ is the correct choice.