If pumping the brake pedal does not work to fix a stuck brake pedal, what is the next step you should take?

Using the emergency or parking brake gently is the appropriate next step if pumping the brake pedal does not resolve a stuck brake pedal issue. The emergency brake is designed to provide extra stopping power and can help to slow down the vehicle safely without the reliance on the main brake system, which is compromised in this situation. It allows for controlled deceleration, enabling the driver to maintain better control over the vehicle while looking for a safe place to pull over or stop.

Utilizing the emergency brake should be done with care to avoid skidding or losing control, as it can cause the rear wheels to lock up if applied too forcefully. This method helps to manage the vehicle’s speed until the driver can stop safely.

The other options involve actions that may not prioritize vehicle control or safe stopping. Turning off the ignition might seem like a solution, but it can result in additional issues, like losing power steering and power brakes, making it harder to control the vehicle. Trying to pull over immediately without using the emergency brake can create a dangerous situation if the main brakes are ineffective. Calling for roadside assistance can be a valid action, but it's best utilized after safely slowing down the vehicle. Therefore, using the emergency brake is the most effective and safe immediate response in this scenario.