This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cardiovascular system, Subject name: Pharmacology
Glyceryl trinitrate route of administration 
Select and explain. 
A. Oral, B. Submucosal, C. Rectal, D. Sublingual
D: Sublingual
Answer: D: Sublingual 
Explanation: GTN is usually given by SL route .kept under the tongue and can be spit it out when sufficient pain relief is obtained.SL-1st pass metabolism can be bypassed. Ref: KD Tripathi 8th ed.