A 13-month-old boy is brought to the physician because of lethargy and irritability for the past 2 days. He was diagnosed with middle ear infection 3 days ago and treated with antibiotics. Laboratory studies show metabolic acidosis and an increased plasma valine concentration. Which of the following amino acid concentrations are most likely to be increased in this patient's blood if he has maple syrup urine disease? A) Arginine and lysine B) Asparagine and glutamine C) Homocysteine and cysteine D) Leucine and isoleucine E) Phenylalanine and tyrosine