Final answer:
The effect of stress on urine output is decreased urine output, due to the increased release of antidiuretic hormone and elevated aldosterone levels.
Step-by-step explanation:
The effect of stress on urine output is decreased urine output. When a person is under stress, the stress response releases an increased amount of antidiuretic hormone (ADH) and elevates aldosterone levels. ADH increases water reabsorption, while aldosterone causes sodium and water retention. Both of these physiological responses reduce urine output.