question: Q:A 45-year-old man presents to his primary care physician complaining of increasingly frequent headaches. He also reports that his hats and wedding ring do not fit anymore. His temperature is 99°F (37.2°C), blood pressure is 145/80 mmHg, pulse is 85/min, and respirations are 16/min. Physical examination is notable for frontal bossing, a prominent jaw, and an enlarged tongue. A chest radiograph reveals mild cardiomegaly. Serum insulin-like growth factor 1 levels are significantly elevated. Which of the following conditions is this patient at greatest risk for?? 
  {'A': 'Pheochromocytoma', 'B': 'Medullary thyroid carcinoma', 'C': 'Osteoid osteoma', 'D': 'Carpal tunnel syndrome', 'E': 'Osteosarcoma'},