Before changing lanes on a multi-lane highway, what should you do?

Checking your mirrors and blind spots before changing lanes on a multi-lane highway is essential for ensuring safety. This step allows you to be aware of surrounding traffic, including vehicles that may be in your blind spots that are not visible in your mirrors. By thoroughly assessing your surroundings, you minimize the risk of collisions and create a safer environment for yourself and other drivers.

It's important to note that the other options do not adequately promote safety. Using your horn may startle other drivers without effectively communicating your intention. Accelerating to change lanes quickly might create a hazardous situation if other vehicles are too close, and signaling only if it's safe contradicts the standard practice of indicating your intent to change lanes beforehand. Signaling ahead of time helps inform other drivers to anticipate your move, thereby enhancing overall roadway safety.