In which of the following systems does stress incontinence occur as one ages?

Stress incontinence occurs primarily in the urinary system. This condition is characterized by the involuntary leakage of urine that occurs when pressure is applied to the bladder, such as during activities like coughing, sneezing, laughing, or exercising. As individuals age, the pelvic floor muscles and tissues that support the bladder can weaken, contributing to stress incontinence. Additionally, hormonal changes, particularly in women after menopause, can further impact the strength and elasticity of these tissues, making incontinence more likely.

The other systems mentioned do not typically relate to the mechanisms causing stress incontinence. For instance, the digestive system primarily deals with the processing of food and waste, while the respiratory system focuses on gas exchange and breathing. The sensory system is involved in processing sensory information but is not associated with urinary control. Therefore, the urinary system is the only one directly connected to issues like stress incontinence, especially as it relates to physiological changes that occur with aging.