This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Infection, Subject name: Medicine
[{'content': '"Break bone fever" is: \nSelect and explain. \nA. Rheumatic fever, B. Dengue fever, C. Rat-bite fever, D. Relapsing fever', 'role': 'user'}, {'content': 'Answer: B \nExplanation: (Dengue fever): Ref: 111, 1164-H (1230-H17th)DENGUE FEVER: - Caused by (4 - serotype) Aedes - aegpti (flavi virus)* Headache, musculoskeletal pain ("break bone fever"): leukopenia occasionally biphasic ( "saddleback") fever* Macular rash on the first day, as well as adenopathy, palatal vesicles and scleral injection* Epistaxis and scattered petectiae are often noted in uncomplicated dengue, and preexisting GI lesion may bleed during the acute illness* Leucopenia, thrombocytopenia and increased aminotransferase', 'role': 'assistant'}]