This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Forensic Medicine
The active principle 
Select and explain. 
A. Nicotine, B. Nerin, C. Abrine, D. Pilocarpine
B: Nerin
Answer: B: Nerin 
Explanation: Ans. b. Nerin