question: Q:A 22-year-old man comes to the physician because of headaches and blurry vision for the past 6 months. He also reports frequent episodes of vomiting over the last month. His father has died of renal cell carcinoma at the age of 37 years. Examination shows 20/40 vision bilaterally. Fundoscopic examination shows bilateral optic disc swelling and growth of capillary vessels in the temporal peripheral retina. An MRI of the brain shows an infratentorial mass. The patient undergoes surgical resection of the mass. A photomicrograph of the resected specimen is shown. Which of the following is the most likely diagnosis?? 
  {'A': 'Medulloblastoma', 'B': 'Glioblastoma', 'C': 'Oligodendroglioma', 'D': 'Hemangioblastoma', 'E': 'Ependymoma'},