Final answer:
When meeting a vehicle at night with only one headlight, you should reduce your speed and be cautious due to a potential problem with the vehicle's headlights.
Step-by-step explanation:
When meeting a vehicle at night with only one headlight, you should not ignore it. Instead, you should reduce your speed and be cautious because the vehicle may be experiencing a problem with its headlights. By reducing your speed and maintaining a safe distance, you can ensure your safety as well as the safety of other drivers on the road.