Why is it important to signal before changing lanes?

Signaling before changing lanes is crucial because it communicates your intended actions to other drivers on the road. When you signal, you provide a warning and allow those around you to anticipate your next move, which significantly reduces the risk of collisions. Other drivers can respond appropriately by adjusting their speed or position, fostering a safer environment on the road.

In contrast, the other choices do not relate to the primary purpose of signaling. Sharing your driving history, indicating your vehicle's speed, or showing its color does not inform other road users about your lane change intentions and does not contribute to traffic safety. The primary function of signaling is to enhance communication between drivers, ensuring everyone is aware of one another's actions.