Whenever any roadway has been divided into two or more clearly marked lanes for traffic, the following rules, in addition to all other consistent herewith, shall apply:
(A) A vehicle shall be driven as nearly as practicable entirely within a single lane and shall not be moved from such lane until such movement can be made with safety. Where other traffic may be affected, appropriate signals shall be exhibited.
(B) Official signs may be erected directing slow-moving traffic to use a designated lane or designating those lanes to be used by the traffic moving in a particular direction regardless of the center of the roadway, and drivers of vehicles shall obey the directions of every such sign.
('74 Code, § 9-5-4.41) (Ord. 65-1974)