Elderly patients experience postural hypotension, which is a sign of aging related to the ____.

A) integumentary system
B) musculoskeletal system
C) nervous system
D) cardiovascular system
E) special senses

Postural hypotension, also known as orthostatic hypotension, is a condition where blood pressure drops significantly upon standing up from sitting or lying down. It is related to the cardiovascular system because this system is responsible for maintaining blood pressure and blood flow throughout the body. Aging can affect the cardiovascular system's ability to quickly adjust blood pressure, leading to postural hypotension in elderly patients.