This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Parasitology Pa 1 (Protozoology), Subject name: Microbiology
[{'content': 'The main reservoir for Entamoeba histolytica is - \nSelect and explain. \nA. Man, B. Diy water, C. Soil, D. Ponds', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The main reservoir for Entamoeba histolytica is man. Other options can be the modes of transmission ie. faeco oral through contaminated water. Option 1, 2, 3, 4 E. histolytica: Habitat: Large intestine Morphology-3 stages: Trophozoites, Pre-cyst and cyst. Host: Humans are the only host and reservoir. Infective form: Mature quadrinucleate cyst. Mode of transmission: Faeco-oral route and rarely sexual transmission (20-30% in homosexuals).', 'role': 'assistant'}]