This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
Hemoglobin dissociates into bilirubin forming the following intermediate product: 
Select and explain. 
A. Biliverdin, B. Bilirubin diglucuronide, C. Urobilin, D. Stercobilin
A: Biliverdin
Answer: A: Biliverdin 
Explanation: None