This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Substance abuse, Subject name: Psychiatry
[{'content': 'All are seen in nicotine withdrawal except \nSelect and explain. \nA. Hyperhydrosis, B. Anxiety, C. Bradycardia, D. Insomnia', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Nicotine withdrawal can occur 12-14 hours after last smoke and can present with anxiety, restlessness, poor concentration, decreased sleep, increased appetite and exacerbation of psychiatric symptoms in those with the pre-existing psychiatric disorder(s). Ref: A Sho Textbook of Psychiatry, Niraj Ahuja, 7th Edition, pg. no.52', 'role': 'assistant'}]