(a) A person who commits the offense of forgery in the first degree shall be guilty of a felony and, upon conviction thereof, shall be punished by imprisonment for not less than one nor more than 15 years.
(b) A person who commits the offense of forgery in the second degree shall be guilty of a felony and, upon conviction thereof, shall be punished by imprisonment for not less than one nor more than five years.
(c) A person who commits the offense of forgery in the third degree shall be guilty of a felony and, upon conviction thereof, shall be punished by imprisonment for not less than one nor more than five years.
(d) A person who commits the offense of forgery in the fourth degree shall be guilty of a misdemeanor; provided, however, that upon the third and all subsequent convictions for such offense, the defendant shall be guilty of a felony and shall be punished by imprisonment for not less than one nor more than five years.