Tattoing in entry wound of a firearm injury is due to-
**Core Concept**
Tattoing in entry wounds refers to the radial pattern of soot particles or unburnt gunpowder around the wound, resulting from the explosive combustion of the firearm's propellant. This phenomenon occurs due to the rapid expansion of gases from the gunshot, which disperses the particles in a radial direction.
**Why the Correct Answer is Right**
The correct answer is related to the mechanism of firearm discharge and the physical properties of gases. When a firearm is discharged, the rapid combustion of the propellant produces high-pressure gases that expand rapidly through the barrel. As these gases exit the barrel, they carry soot particles or unburnt gunpowder with them, dispersing them in a radial pattern around the wound. This results in the characteristic tattooing or stippling seen in entry wounds.
**Why Each Wrong Option is Incorrect**
* **Option A:** Incorrect because tattooing is not a result of the bullet's kinetic energy or its interaction with the skin.
* **Option B:** Incorrect because the bullet's size and shape do not directly influence the presence of tattooing in entry wounds.
* **Option C:** Incorrect because the distance between the firearm and the target does not affect the presence of tattooing, although it may affect the wound's size and characteristics.
**Clinical Pearl / High-Yield Fact**
Tattooing in entry wounds is often seen in close-range firearm injuries, typically within 6-8 inches of the target. This is because the high-pressure gases produced by the firearm's discharge are able to carry soot particles and unburnt gunpowder over short distances.
**Correct Answer: C. Powder tattooing.**