What is the implication of not releasing the hand brake before starting?

Not releasing the hand brake before starting the vehicle significantly impacts control. When the hand brake is engaged, it prevents the rear wheels from moving. As a result, the vehicle may not roll freely, which can lead to difficulties in maneuverability and handling. In a situation where you attempt to start the engine without disengaging the hand brake, the engine may struggle to turn the wheels, causing a delayed response and potentially leading to a loss of control, especially if the driver is not expecting the vehicle to remain stationary.

While some of the other options might seem plausible, they do not capture the critical aspect of control. For instance, the vehicle would not accelerate quickly due to the brake being engaged, and maintaining speed or assisting in engine cooling does not relate to the immediate consequence of not releasing the hand brake before starting the vehicle. Overall, understanding vehicle control is essential for safe driving practices.