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: Pharmacology
Following drug which undergo most of its metabolism presystemically: 
Select and explain. 
A. Salbutamol, B. Verapamil, C. Propranolol, D. Paracetamol
C: Propranolol
Answer: C: Propranolol 
Explanation: None