This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General physiology, Subject name: Physiology
Ca2+ Channel blockers would have a significant effect on muscle function in 
Select and explain. 
A. Skeletal muscle, B. Smooth muscle, C. Both the above, D. Neither
B: Smooth muscle
Answer: B: Smooth muscle 
Explanation: The calcium-channel blockers represent a group of organic chemical structures that share the ability to inhibit Ca2+ entry into excitable cells. ... Thus, calcium-channel blockers are smooth-muscle dilators and have a negative inotropic effect on the working myocardial cells of the atria and ventricles Ref guyton and hall textbook of medical physiology 12/e pg 73