About seven months ago, 15-year-old Katie went on a drastic weight-loss diet that caused her to drop from 110 to 85 pounds. Although she is now dangerously underweight and undernourished, she continues to think she looks fat. Katie most clearly suffers from what psychological disorder?
A Abnormally low set point
B Anorexia nervosa
C Bulimia nervosa
D Hypermetabolism
E Homeostatic disruption