Sudden braking is permitted when:
- Correct answer: It is the only way to prevent an accident.
- The driver or any of the passengers suddenly want to get off the vehicle.
- The driver wants to make a U-turn.
- The driver realizes he is lost.
Why this is the answer
The correct answer in the official bank: It is the only way to prevent an accident.
Sudden braking endangers the vehicles behind you, which may crash into you, and can also hurt your own passengers. It is allowed only when it is the only way to prevent an accident. Getting lost, wanting to get off or planning a U-turn never justify it. In those cases slow down gradually, signal and stop or turn where it is safe and permitted.