This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
[{'content': 'Therapeutic uses of prostaglandin E1  include all of the following; except \nSelect and explain. \nA. Medical termination of pregnancy, B. Impotence, C. Primary pulmonary hypertension, D. Maintenance of patent ductus arteriosus', 'role': 'user'}, {'content': 'Answer: C \nExplanation: PGI2 analogs (like epoprostenol and treprostinil) are used for treatment of pulmonary hypertension.\nPGE1 analogs are used for first trimester abortion (misoprostol), impotence (alprostadil) and maintenance of the patency of ductus arteriosus (alprostadil).', 'role': 'assistant'}]