During a traffic stop, an officer noticed a pistol on the passenger seat of the car. While inspecting the weapon to see if it was loaded, the officer saw that the identification numbers had been removed and a name had been stamped in that location on the firearm. The man explained that the handgun had belonged to his grandfather who had given it to him as a special keepsake. The man went on to explain that he had removed the numbers and replaced them with his grandfather's name as a tribute. What crime, if any, occurred?
a) Tampering with evidence
b) Possession of a firearm with altered identification marks
c) Grand theft firearm
d) Illegal possession of a firearm