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
[{'content': 'Which of the following is not used in the treatment of Pulmonary hypeension \nSelect and explain. \nA. Calcium channel blockers, B. Alpha blockers, C. Prostacyclin, D. Endothelin receptor antagonist', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Refer CMDT 2010/381 management of of idiopathic Pulmonary hypeension if the patient respond to vasodilators the Calcium channel blockers (including amlodipine diltiazem and Nifedipin) are the first line agents of drugs other drugs that can be used are phosphodiesterase inhibitors(sildenafil) Prostacyclin analogue(epoprostenol) Endothelin receptor blockers(bosenton)', 'role': 'assistant'}]