This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Pharmacology
Mechanism of action of levosimendan include: 
Select and explain. 
A. Na channel opener, B. K channel opener, C. Beta blocker, D. Beta 1 agonist
B: K channel opener
Answer: B: K channel opener 
Explanation: Ans. (B) K channel opener(Ref: Katzung 11th/e p.221)Levosimendan is an inodilator that act by[?]Ca2+ sensitizing action by binding to troponin-C (inotropic action)[?]K+ Channel opening action -- (responsible for vasodilation)