What does the center line indicate on a two-lane road?

• A. A bicycle lane
• B. The separation of traffic traveling in opposite directions
• C. The edge of the road
• D. The boundary of the shoulder

Answer: (B)

The center line on a two-lane road serves to separate traffic moving in opposite directions, guiding drivers to stay in their lane and avoid crossing into oncoming vehicles. This line is the primary marker for how traffic is divided and, depending on its style, can indicate whether passing is allowed (dashed) or prohibited (solid). That direct purpose makes it the best answer. A bicycle lane is typically marked toward the edge of the road with bike symbols, not in the center. The edge of the road and the boundary of the shoulder are not about opposing-direction separation, and are marked differently.