Definition of hallucination -

Ans. is 'a' i.e., Perception witout stimulus o Disorder of perception may be : -Altered perception : - There is alteration of preception of a real external stimulus. It may be : -Sensory distortion : - There is change in the intensity of a real external stimulus. For example micropsia (perceiving a real object smaller than its normal size) and hyperacusis (perceiving sounds as abnormally loud).Illusion : - There is misinterpretation of a real external stimulus. For example mistaking a stick for snake.False perception : - There is an internal perception without a real external stimulus, e.g., Hallucination and pseudo-hallucination