This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: parasitology, Subject name: Microbiology
A child from Bihar comes with fever. Blood examination shows sheathed microfilaria with nuclei up to tail tip. The diagnosis is - 
Select and explain. 
A. B. Malayi, B. W. Bancrofri, C. Loa loa, D. Oncocerca volvulous
A: B. Malayi
Answer: A: B. Malayi 
Explanation: Mf malayi Smaller Kinky with secondary curves Twice as long as broad Double stylet present Two distinct nuclei,one terminal and the other subterminal (refer pgno:170 baveja 3 rd edition)