Question

to ensure the lane next to you is clear when you want to change lanes, you should: turn your head and look over the right shoulder look into the rearview mirror only turn your head and look in the lane you are going to enter turn your head and look over your left shoulder

Explanation:

To ensure the lane next to you is clear when changing lanes, you need to check the target lane directly. Looking only in the rearview mirror (second option) is insufficient as blind spots exist. Looking over a specific shoulder (first, fourth options) is not as comprehensive as looking into the lane you're entering. The correct method is to turn your head and look in the lane you are going to enter to check for vehicles in the blind spot and the lane's overall clarity.

Answer:

The correct option is: Turn your head and look in the lane you are going to enter