<prompt> Withdrawal of which of the following causes piloerectionMorphineCannabisSmokingAlcohol  <response>: Opioid withdrawal: The characteristic symptoms include lacri mation, rhinorrhoea, pupillary dilation, sweating, diarrhoea, yawning, tachycardia, mild hyper tension, insomnia, raised body temperature, muscle cramps, generalised bodyache, severe anxiety, piloerection, nausea, vomiting and anorexia. Ref: Ahuja Sho textbook of psychiatry by Niraj Ahuja 7th edition, page 43. 