Refer to the Diagram; On a road project, lanes A and B flow in the same direction and are opposite of lanes C and D that flow in the same direction. If a driver in Lane A cannot merge into lane B and a driver in lane B cannot merge into lane A, what type of line is between lanes A and B?

Refer to the Diagram; On a road project, lanes A and B flow in the same direction and are opposite of lanes C and D that flow in the same direction. If a driver in Lane A cannot merge into lane B and a driver in lane B cannot merge into lane A, what type of line is between lanes A and B?