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: Forensic Medicine
When 34 year old police officer fired the gun, bullet didn't come out, so he fired again, now first bullet comes out along with second bullet. This pattern of two bullets coming out of muzzle end in called? 
Select and explain. 
A. Duplex bullet, B. Tandem bullet, C. Dum-Dum bullet, D. All of the above
B: Tandem bullet
Answer: B: Tandem bullet 
Explanation: None