What should you do before changing lanes?

Answer: A — Check your mirrors and look over your shoulder

Before changing lanes, it is crucial to check your mirrors and look over your shoulder. This practice ensures that you are fully aware of your surroundings and can identify any vehicles that may be in your blind spot or approaching quickly. Checking your mirrors gives you a broad overview of the lane next to you, while looking over your shoulder provides a more precise view of any vehicles that may not be visible through your mirrors. Taking these steps helps prevent accidents and enhances road safety. It's important to be vigilant and confirm that the lane is clear before making any lane changes, as this reduces the risk of colliding with another vehicle or causing traffic disruptions.