This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Medicine
[{'content': "True about Rheumatic hea disease and Rheumatic fever is/are - \nSelect and explain. \nA. Caused by group 'A' streptococci, B. Caused by group 'B' streptococci, C. Carrier have high risk of developing RF, D. Carrier have low risk of developing RF", 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ref: R Alagappan - Manual of Practical Medicine 4th Edition.pg no: 146 Rheumatic Fever Acute, recurrent, inflammatory disease, mainly of children (aged 5-15 years), typically occurring 1-5 weeks after group A streptococcal infection. Pathophysiology 1. Cross reactivity of host antistreptococcal antibodies to cardiac antigens 2. Microbe initiated autoimmune reactivity.', 'role': 'assistant'}]