A 35-year-old female client who complains of weight gain, facial hair, absent menstruation, frequent bruising, and acne is diagnosed with Cushing's syndrome. Cushing's syndrome is most likely caused by which of the following
A．An ectopic corticotropin-secreting tumor.
B．Adrenal carcinoma.
C．A corticotropin-secreting pituitary adenoma.
D．An inborn error of metabolisrn.
