A patient with total incontinence has a complete lack of:

The correct choice indicates that a patient with total incontinence has a complete lack of bowel or bladder control. Total incontinence refers specifically to the inability to control urination and/or defecation, which results in involuntary loss of urine or feces. Understanding this condition is crucial because total incontinence can significantly impact a patient's quality of life and require specific care interventions to manage hygiene, skin integrity, and dignity.

In contrast, the other options address different aspects of physical health and function. Ambulation refers to the ability to walk, which is not directly related to incontinence. Blood pressure is a vital sign that measures the force of blood against the artery walls and does not pertain to incontinence. Mobility refers to the ability to move freely and easily, which, while potentially affected by other health issues, is not synonymous with incontinence itself. Thus, the focus on bowel or bladder control is essential in recognizing and addressing the needs of someone with total incontinence.