What document must you carry at all times while driving?

To legally operate a vehicle, it is essential to have your driver's license with you at all times. The driver's license serves as proof that you have been authorized to drive and have met the necessary requirements, such as passing driving tests and adhering to traffic laws. Without it, you may face penalties, including fines or even being charged with driving without a license.

While the other documents listed—vehicle registration, proof of insurance, and an identification card—are important for various reasons, they do not carry the same legal requirement to be present in the vehicle at all times. Vehicle registration is essential for proving ownership and that the vehicle is legally registered, proof of insurance is crucial for financial responsibility in case of an accident, and the identification card can serve as an alternative form of ID but is not necessary when you already have a driver's license. Therefore, carrying your driver's license is the most critical requirement when driving.