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: Pharmacology
Nitroglycerine cannot be administered by which of the following route: 
Select and explain. 
A. I.M., B. I.V., C. Oral., D. Sublingual.
A: I.M.
Answer: A: I.M. 
Explanation: None