This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Forensic Medicine
Nitroguanidine is used as a propellant cahrge in 
Select and explain. 
A. Semismokeless gun powder, B. Single based smokeless gun powder, C. Double based smokeless gun powder, D. Triple based smokeless gun powder
D: Triple based smokeless gun powder
Answer: D: Triple based smokeless gun powder 
Explanation: Triple base powder consists of nitrocellulose, nitroglycerin, and nitroguanidine. The quantity of nitroglycerin is small but sufficient to give power; the nitroguanidine lowers the flame temperature while adding an active explosive constituent. Ref - Krishan Vij textbook of forensic medicine and toxicology 5e pg - 239