What should you do to avoid a head-on collision if an oncoming vehicle is in your lane?

Answer: B — Steer right toward the shoulder or curb-line

Steering right toward the shoulder or curb-line is the recommended action to take in the event of an oncoming vehicle encroaching into your lane. This maneuver gives you the best chance to create space between your vehicle and the potential collision, allowing you to safely avoid the head-on impact. By steering right, you can utilize the shoulder of the road, which is often designed to provide a buffer zone that can help keep you safe. Additionally, this action can help you maintain control of your vehicle while minimizing the chances of swerving into opposing traffic or losing control. Stopping in your lane could place you at greater risk, as it may not effectively prevent the oncoming vehicle from colliding with you. Furthermore, accelerating toward the vehicle would only increase the severity of a potential collision. Steering left towards the center does not help in this scenario, as it would bring you closer to the oncoming vehicle. Hence, steering right is the most appropriate and effective response.