This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Central Nervous system, Subject name: Pharmacology
An addict presents with increased sweating, lacrimation, diarrhea, yawning and rhinorrhea. These symptoms may occur due to withdrawal of: 
Select and explain. 
A. Heroin, B. Cocaine, C. Cannabis, D. Alcohol
A: Heroin
Answer: A: Heroin 
Explanation: Ref:Kaplan and Sadocks synapsis of psychiatry/448 *Opioid withdrawal presents with dysphoric mood, nausea, vomiting, muscle aches, lacrimation, sweating and yawning.it is also called "Cold Turkey". *Cocaine withdrawal presents with dysphoric mood, fatigue, vivid and unpleasant dreams, insomnia or hypersomnia psychomotor agitation or retardation. *Cannabis is not associated with withdrawal syndrome. *Alcohol withdrawal presents with sweating,pulse rate >100, hand tremors, insomnia, transient visual/tactile/auditory hallucination, it can progress to grand mal seizures and delirium tremens.