Final answer:
Ammunition residue describes traces left after firing a firearm, consisting of various particles and substances from the bullet, casing, and propellant.
Step-by-step explanation:
The term ammunition residue refers to c) Traces left after firing a firearm. These residues can include particles from the bullet, the casing, the propellant, and primer, among other things. They are often analyzed in forensic investigations to determine if a person has discharged a firearm. Ammunition residue is neither odorless, colorless, nor in liquid form; rather, it consists of various small particles and substances deposited on the hands, clothing, or surfaces near the discharged firearm.