Final answer:
Health is the subject that undergoes change in response to life-altering events. Health psychologists study how biological, psychological, and sociocultural factors affect health and research ways to improve health through intervention and education.
Step-by-step explanation:
The subject that undergoes change in response to life-altering events is Health. Health is affected by the interaction of biological, psychological, and sociocultural factors. Health psychologists study how genetic makeup, patterns of behavior, relationships, and psychological stress impact health. They also research effective ways to motivate individuals to address behaviors that contribute to poorer health.