Pharmacology Mechnism of action of sildenafil – A Inhibition of adenosine deaminase B Inhibition of phosphodiesterase-5 C Inhibition of Aminopeptidase D Inhibition of Guanylyl cyclase 💡 Explanation Mechnism of action of sildenafil - ✓ Correct Answer: B. Inhibition of phosphodiesterase-5