question: Q:An inconsolable mother brings her 2-year-old son to the emergency room after finding a large amount of bright red blood in his diaper, an hour ago. She states that for the past week her son has been having crying fits while curling his legs towards his chest in a fetal position. His crying resolves either after vomiting or passing fecal material. Currently, the child is in no apparent distress. Physical examination with palpation in the gastric region demonstrates no acute findings. X-ray of the abdominal area demonstrates no acute findings. His current temperature is 36.5°C (97.8°F), heart rate is 93/min, blood pressure is 100/64 mm Hg, and respiratory rate is 26/min. His weight is 10.8 kg (24.0 lb), and height is 88.9 cm (35.0 in). Laboratory tests show the following:
  RBC count 5 million/mm3
  Hematocrit 36%
  Hemoglobin 12 g/dL
  WBC count 6,000/mm3
  Mean corpuscular volume 78 fL
  What is the most likely cause of this condition?? 
  {'A': 'Failure of the vitelline duct to open', 'B': 'Failure of the vitelline duct to close', 'C': 'Problem with bilirubin conjugation', 'D': 'Problem with bilirubin uptake', 'E': 'Elevated anti-mitochondrial uptake'},