A 21-year-old woman, high school graduate, with an eating disorder since the age of 13-years-old and with a diagnosis of anorexia nervosa since the age of 19-years-old, comes to the physician for a follow up after receiving 12-bifrontotemporal electroconvulsive therapy (ECT) treatments secondary to her BMI falling to 12.2. Since the treatments, her BMI has risen to 14.6, her mood is slightly better, she has started to smile, but she has started lying, stealing and hysterical cutting. The patient is most likely using which of the following defense mechanisms?
A. Acting out
D. Reaction formation