Your 89-year-old male patient has called for help because he almost passed out after bringing in his garbage cans from the curb. The patient lives alone and says that he became panicked when he started feeling so lightheaded and dizzy. Patients in this age group often undergo all of the following changes to their health, except:

A) sleep-wake cycle disrupted. B) deterioration of respiratory system.
C) increased metabolism. D) blood volume decreases.

C