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
In firearm injury, entry-wound blackening is due to : 
Select and explain. 
A. Flame, B. Hot gases, C. Smoke, D. Unburned powder
C: Smoke
Answer: C: Smoke 
Explanation: C i.e. Smoke - The blackening of entery wound is due to fine carbon paicles in smokeQ. Grease (abrasion) collar is seen in firearm entry woundQ. - Bevelling of skull is seen in exit wound (point) of bulletQ.