When can a driver legally overtake another vehicle?

Answer: B — Only when the road markings permit passing and it's safe

A driver can legally overtake another vehicle only when the road markings permit passing and it's safe to do so. This is based on traffic regulations designed to ensure safety and proper traffic flow. Road markings, such as solid or dashed lines, provide visual guidance on where overtaking is allowed. A dashed line typically indicates that overtaking is permitted, while a solid line indicates that it is not. Moreover, safety is paramount; a driver must assess the road conditions, visibility, and speed of oncoming traffic before making the decision to overtake. This ensures that overtaking does not pose a risk to themselves or other road users. Overtaking in unsafe conditions can lead to accidents, which is why adherence to these rules is crucial for maintaining road safety. In scenarios like heavy traffic or at a red light, those options do not account for proper overtaking etiquette or the potential hazards these situations present. Thus, following the road markings and ensuring it's safe to pass is the correct and responsible approach to overtaking another vehicle.