challenge: What is a characteristic feature of Histidinuria-renal tubular defect syndrome?
  
  A. Increased ability to absorb arginine in the liver
  B. Impaired ability to absorb histidine in the intestines and renal tubules
  C. Reduced ability to absorb lysine in the pancreas
  D. Impaired ability to absorb tryptophan in the kidneys
  Answer: 