This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Parasitology Pa 2 (Helminthology), Subject name: Microbiology
[{'content': 'A child from Bihar was brought to OPD with fever. On blood examination,sheathed microfilaria with two nuclei in tail tip is seen . The diagnosis is: \nSelect and explain. \nA. B.malayi, B. W.bancrofti, C. Loa loa, D. Oncocerca volvulous', 'role': 'user'}, {'content': 'Answer: A \nExplanation: This is the characteristic feature of microfilaria of Brugia malayi. Adults localise in the lymphatics and female lays microfilaria Shows nocturnal periodicity, Sheathed, have a non-continuous row of blurred nuclei throughout the length of the body. There are two terminal nuclei in the tail that are distinctly separated from the other nuclei.', 'role': 'assistant'}]