Final answer:
The General Adaptation Syndrome (GAS) states that stress occurs in three stages: alarm, resistance, and exhaustion.
Step-by-step explanation:
The principle that states we all undergo stress in three stages - the "alarm stage," the "resistance stage," and the "exhaustion stage" - is known as the General Adaptation Syndrome (GAS). According to Hans Selye's three-stage model, the alarm reaction is the body's immediate response to a threatening situation or emergency. The stage of resistance is a period of adaptation where the body adjusts to the stressor. Finally, in the stage of exhaustion, prolonged stress can lead to physical damage and diseases.