What should you do before leaving your vehicle unattended?

Ensuring the safety and security of your vehicle before leaving it unattended is crucial, which is why applying the parking brake and securing the vehicle is the correct action to take. Engaging the parking brake prevents the vehicle from rolling away, providing a critical safety measure, especially on inclines or uneven surfaces. Securing the vehicle by ensuring it is stationary and stable can help avoid accidents or damage, and reduces the risk of theft or unauthorized use.

In addition to securing the vehicle, it's important to consider other relevant steps such as turning off the engine and locking the doors and windows. However, the focus here is on securing the vehicle first to maintain control and safety before addressing other considerations. Leaving the engine running is not advisable, as it poses safety risks and is often illegal in many areas.