This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cardiovascular system, Subject name: Pharmacology
The following Potassium channel opener is used in angina 
Select and explain. 
A. Nicorandil, B. Hydralazine, C. Fasudil, D. Ranolazine
A: Nicorandil
Answer: A: Nicorandil 
Explanation: Nicorandil, minoxidil, pinacidil are potassium channel openers used in angina which produce hyperpolarization. and causing the vasodilation and reducing the oxygen demand and increase the oxygen supply yo the infracted area. Ref: KD Tripathi 8th ed.