A. A motor vehicle owned by or operated under contract to a utility, whether privately or publicly owned, when used in the construction, operation, removal or repair of utility property or facilities or engaged in authorized work in the designated residential parking permit area;

B. A motor vehicle identified as owned by or operated under contract to a governmental agency and being used in the course of official government business;

C. A commercial vehicle, private vehicle or trailer while loading or unloading property, or when such vehicle is parked in connection with or in aid of the performance of a service to or on real property in the residential parking permit area in which such commercial vehicle, private vehicle or trailer is parked;

D. Any authorized emergency vehicle as defined by California Vehicle Code Section 165.