Which of the following can impair a person's ability to drive safely?

Consuming alcohol or drugs significantly impairs a person's ability to drive safely because they can alter judgment, reaction times, coordination, and overall cognitive function. Alcohol is known to slow down the central nervous system, affecting motor skills and reducing an individual's ability to assess situations accurately. Similarly, many drugs—both prescription and illegal—can have effects that distract or impair mental acuity, making it challenging to respond appropriately to the fast-paced environment of driving.

In contrast, being well-rested, maintaining focus on the road, and having an experienced passenger contribute positively to safe driving by enhancing alertness, attention, and decision-making skills. A well-rested driver is more capable of processing information and reacting swiftly to changes in traffic conditions. Staying focused on the road ensures that the driver is aware of their surroundings, while an experienced passenger can act as an additional set of eyes and provide helpful advice during the journey.