**Question:** Gun powder in hand during gun-shot residue is collected using:-

A. Cotton swab
B. Magnetic field
C. Wooden stick
D. Fabric tape

**Core Concept:** Gun-shot residue (GSR) is a collection of particles released from a firearm during discharge. GSR analysis is used to determine if a person has handled a firearm recently.

**Why the Correct Answer is Right:** D. Fabric tape is the correct method for collecting GSR because it is designed to adhere to the skin and pick up the particles, ensuring efficient collection and minimal contamination. Fabric tape is made of a non-porous material that prevents the particles from being absorbed into the tape.

**Why Each Wrong Option is Incorrect:**

A. Cotton swab (Option A): Cotton swabs are porous and can absorb the particles, leading to incomplete collection and potential contamination with other substances.
B. Magnetic field (Option B): Gun-shot residue is not attracted by a magnetic field, making this method inefficient for collection.
C. Wooden stick (Option C): Wooden sticks are not designed for particle collection and do not effectively pick up GSR particles.

**Clinical Pearl:** Gunshot residue analysis is a crucial tool in forensic investigations, particularly in cases involving firearm-related crimes.

**Correct Answer:** D. Fabric tape (Fiberfix) is the optimal method for collecting gun-shot residue from the skin surface.