This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Mental Health, Subject name: Social & Preventive Medicine
[{'content': 'Rope mistaken for a snake, is an example of - \nSelect and explain. \nA. Illusion, B. Delusion, C. Hallucination, D. None', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e. Illusion Illusiono Illusions are altered perception in which a real external object is combined with imagery to produce false internal percept. In simple words, illusion is misinterpretation of an actual sensory input. For example:-i) Mistaking a stick or rope for snake in dark room:- Stick is a real external object, which is perceived falsely as snake.ii) Hearing once name in a train whistle:- Train whistle is a real external stimulus, which is perceived as once name (false internal percept).In illusion:-i) Sensory input is in external atmosphere.ii) Percept is in internal atmosphere (inner subjective space, i.e., inside the mind)o Illusions are most commonly seen in delirium.", 'role': 'assistant'}]