You are answering a USMLE-style medical question. Question: A 55-year-old woman with papillary thyroid carcinoma underwent total thyroidectomy. She has no significant medical history. On postoperative day 1, she develops perioral numbness and a tingling sensation, along with paresthesia of the hands and feet. The physical examination reveals that she is anxious and confused. Her pulse is 90/min, the blood pressure is 110/80 mm Hg, the respirations are 22/min, and the temperature is 36.7°C (98.0°F). Latent tetany (carpal spasm) is evident in the right arm. This is observed when the sphygmomanometer cuff pressure is raised above the systolic blood pressure and held for 3 minutes. The laboratory test results are as follows: Serum calcium 6.7 mg/dL Serum sodium 143 mEq/L Serum potassium 4.4 mEq/L Serum creatinine 0.9 mg/dL Blood urea 16 mg/dL Serum magnesium 1.1 mEq/L What is the most likely cause of this condition? Options: A) Inadvertent surgical removal of parathyroid glands B) DiGeorge syndrome C) Chronic hypomagnesemia D) Hungry bone syndrome Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.