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
Characteristic features of opioid withdrawal is: 
Select and explain. 
A. Rhinorrhea and lacrimation, B. Seizures, C. Delirium tremors, D. Transient visual, tactile or auditory hallucinations
A: Rhinorrhea and lacrimation
Answer: A: Rhinorrhea and lacrimation 
Explanation: Ref: KDT 6/e p447 *Withdrawal symptoms are opposite of the acute effect of drug. For opioids, these include lacrimation, rhinorrhea, lacrimation, yawning, piloerection, diarrhea, nausea, coughing, mydriasis, sweating and twitching of muscles.