Final answer:
Sudden braking or swerving in traffic indicates that a driver may be distracted, following too closely, or driving too fast.
So, the correct answer is option 4.
Step-by-step explanation:
When a driver suddenly brakes or swerves in traffic, it indicates that the driver is not following safe driving practices. This behavior can be caused by distractions, such as using a phone or being preoccupied with something else, which is option 1.
It can also be a result of following too closely to the car in front, giving the driver less time to react, which is option 2. Additionally, driving too fast can make it difficult to stop or maneuver quickly, leading to sudden braking or swerving, which is option 3. Therefore, the correct answer is option 4: All of the above.