This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pathology
Because free ammonia in the blood is toxic to the body, it is transpoed in which of the following non-toxic forms? 
Select and explain. 
A. Histidine and urea, B. Phenylalanine and methionine, C. Glutamine and urea, D. Lysine and glutamine
C: Glutamine and urea
Answer: C: Glutamine and urea 
Explanation: Glutamine and urea Ref: Ganong - Review of Medical Physiology 23rd Ed Page 644