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': 'Riociguat is used for \nSelect and explain. \nA. Pulmonary hypeension, B. Myocarditis, C. Atrial fibrillation, D. Stroke', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Used for Chronic-thromboembolic pulmonary hypeension (CTEPH) and Pulmonary aerial hypeension (PAH) It is a stimulator of soluble guanylate cyclase (sGC). Ref: KD Tripathi 7th ed', 'role': 'assistant'}]