When can you safely return to your lane after passing another vehicle?

The correct answer is based on the importance of ensuring a safe return to your lane after passing another vehicle. You can safely return to your lane when you see the other vehicle’s headlights in your rearview mirror because this indicates that there is sufficient distance between your vehicle and the vehicle you just passed. This distance allows for a safe re-entry into your lane without risking a collision.

Moreover, monitoring the rearview mirror to check for the other vehicle ensures that it has not accelerated or changed lanes unexpectedly while you were passing. Safety is paramount on the road, and this practice helps to maintain that by confirming that the passed vehicle is at a sufficient distance behind you before you merge back into the lane.

Returning when you can no longer see the vehicle or when the road is clear might not account for the situation effectively since the other vehicle could be too close for safety at that moment. It's key to have that visual confirmation of the passed vehicle’s headlights to gauge your safety adequately.