You are answering a USMLE-style medical question. Question: A 17-year-old woman presents to your office concerned that she has not had her menstrual period in 4 months. She states that menses began at age of 13 and has been regular until two months ago. She denies sexual activity, and urine pregnancy test is negative. On exam, she appears well-nourished with a BMI of 21 kg/m^2, but you note that she has enlarged cheeks bilaterally and has calluses on the dorsum of her hands. She says that she has been very stressed with school and has recently been binge eating. What other finding do you expect to see in this patient? Options: A) Malar rash B) Increased blood glucose level C) Erosion of tooth enamel D) Elevated estrogen levels Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.