Many head-on, passing collisions occur because drivers fail to see and accurately judge the of approaching vehicles.

The correct answer would be, Distance.

Explanation:

Many head on, passing collisions occur because drivers fail to see and accurately judge the Distance of the approaching vehicle.

Wrong and inaccurate estimation of distance always lead to head on collisions. Drivers must maintain a good distance between his and other vehicle in order to avoid any accident. Head on collisions or passing collision always occur when drivers cannot estimate the distance of the approaching vehicle.

Safe driving is always necessary, and for this driver should avoid close passes, close overtakes, speedy overtakes, must remain in their lanes, use the indicators while changing the lanes, and must drive slow and carefully in the rush hours and avoid passing through during such times. Drivers must maintain distances between vehicles.

can you give a picture of the map, i'll be able to update my answer!