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
Which of the following drugs cause constipation 
Select and explain. 
A. Propanolol, B. Verapamil, C. Nitroglycerin, D. Captopril
B: Verapamil
Answer: B: Verapamil 
Explanation: Refer kDT 6/e p 530 All Calcium channel blockers can cause smooth muscle relaxation in blood vessels and extravascular organs( bronchus GIT urinary bladder and uterus)