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
Which of the following agents enhances the bioavailability of levodopa in patients with Parkinson's disease : 
Select and explain. 
A. Amantadine, B. Ropinirole, C. Entacapone, D. Selegiline
C: Entacapone
Answer: C: Entacapone 
Explanation: Levodopa metabolized in the body by two enzymes; MAO and COMT. Thus MAO inhibitors like selegiline and COMT inhibitors like entacapone and tolcapone can increase the bioavailability of dopa.