A.   When appropriate traffic control or regulatory signs giving notice of speeds are posted, the maximum speed limits designated upon the signs shall apply to the appropriate streets or portions of streets so posted.
   B.   In the absence of any speed limit sign designating a speed limit applicable thereto, the prima facie speed limit shall be twenty five (25) miles per hour.
   C.   Violations of this section shall constitute a class C misdemeanor and upon conviction, subject to penalty as provided in section 1-4-1 of this code. (1990 Code § 10.04.180; amd. 2003 Code)