(2) A person is not prohibited from driving to the left of the center line of a roadway by this section under the following circumstances:
(a) When authorized by a traffic control device designating certain lanes to the left side of the center of the roadway for use by traffic.
(b) When an obstruction or condition exists making it necessary to drive to the left of the center of the roadway, provided that a driver doing so shall yield the right of way to all vehicles traveling in the proper direction upon the unobstructed portion of the roadway within a distance as to constitute an immediate hazard.
(c) When making a left turn at an intersection, alley or private road or driveway.
(3) The offense described in this section, crossing the center line on a two-way, four-lane road, is a Class B traffic violation. [1983 c.338 §618]