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: Anaesthesia
Dose of ketamine by IM route is (in mg/kg) – 
Select and explain. 
A. 4, B. 6, C. 8, D. 10
A: 4
Answer: A: 4 
Explanation: Different books have given different dose for IM route.