This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Ballistics, Subject name: Forensic Medicine
Bullet that leaves a visible mark in its flight so that person can see the path is 
Select and explain. 
A. Tandem bullet, B. Tracer bullet, C. Dum-dum bullet, D. Incendiary bullet
B: Tracer bullet
Answer: B: Tracer bullet 
Explanation: Tracer bullet: It leaves a visible mark or 'trace' while in flight, so that the path of bullet can be seen . Dum - dum bullet: The nose of the bullet is not covered by jacket & exposed. It expands or mushrooms on striking the target, producing a large hole & more damage. Incendiary bullets: Incendiary bullets contain phosphorus. Type of army bullet used to cause fire in the target. Tandem bullet: Bullets ejected one after the other, when the first bullet having been struck in the barrel fails to leave the barrel and is ejected by a subsequently fired bullet.