What action is prohibited under the safe operation of a vehicle?

Adjusting the radio while driving is prohibited under the safe operation of a vehicle because it diverts a driver's attention from the road. When drivers engage in tasks that require them to take their eyes off the road or hands off the steering wheel, they increase the risk of an accident. Distractions can significantly impair reaction times and decision-making abilities, which are critical for safe driving.

Using seatbelts, on the other hand, is a crucial safety measure and is always encouraged to protect occupants in case of a collision. Similarly, using turn signals is essential for communicating intentions to other road users, which enhances safety by reducing the chances of misunderstandings. Maintaining a safe following distance is a fundamental principle of safe driving, allowing drivers to react appropriately to sudden stops or emergencies. All these actions contribute to a safer driving environment, whereas adjusting the radio can lead to dangerous distractions.