This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cardiovascular Disorders, Subject name: Gynaecology & Obstetrics
[{'content': 'Heart disease in pregnancy, most common - \nSelect and explain. \nA. ASD, B. MS, C. VSD, D. MR', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. is \'b\' i.e., MS "Commonest cardiac lesions are of rheumatic origin followed by congenital ones.""Rheumatic valvular leasion predominantly includes mitral stenosis (MS) "', 'role': 'assistant'}]