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: Microbiology
[{'content': 'Calabar swelling is produced by- \nSelect and explain. \nA. Onchocerca volvulus, B. Loa loa, C. Brugia malayi, D. Wuchereria bancrofti', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Calabar Swelling: Localized angioedema and erythema usually on the extremities, characterized by fugitive, swollen\xa0lumps of subcutaneous tissue caused by a parasitic filarial worm (Loa loa) endemic to Central and West Africa.\nThe swollen areas migrate with the worm through the body at a speed of about 1 cm per minute and may become as\xa0large as a small egg.', 'role': 'assistant'}]