Answer:
c) receptor; control center; effector.
Step-by-step explanation:
Homeostasis maintains the internal body conditions almost constant. It includes specific cells that sense any deviations of internal or external conditions from the normal range. These cells are called receptors. The sensory information from the receptors is delivered to the control center. The central nervous system mainly serves as a control system wherein sensory information from the receptors is processed. The control center commands muscles and/or glands to perform desired responses to restore the homeostasis. Here, muscles and glands serve as effectors.
For example, thermoreceptors sense the rise of body temperature and the brain (control center) commands sweat glands (effectors) to produce sweat.