Final answer:
For safe and courteous driving when lights are required, drivers should switch from high-beam to low-beam lights when following another vehicle within a distance specified by local traffic laws.
Step-by-step explanation:
When lights are required, drivers must switch from high-beam to low-beam lights when following another vehicle within a certain distance. The specific rule can vary by jurisdiction, but common distances are:
- (a) 60 meters
- (b) 90 meters
- (c) 120 meters
- (d) 150 meters
The correct answer to this question requires knowledge of local traffic laws which are not provided in the question context.