You should always travel:
- At the speed of vehicles surrounding you.
- At the speed limit.
- At a speed appropriate for road and weather conditions. ✓
Answer: C. At a speed appropriate for road and weather conditions.
You should always drive at a speed that fits the road and weather conditions, not simply at the posted limit or with the flow of traffic.
Why this is the answer
The handbook explains the Basic Speed Law: you may never drive faster than is safe for the current conditions. It says that regardless of the posted speed limit, your speed should depend on things like how many vehicles are on the road, the road surface, bicyclists or pedestrians, and weather such as rain, fog, snow, wind, or dust. That means the right speed changes with the situation, so matching your speed to the road and weather is the correct approach.
Why the other answers are wrong
- A. At the speed of vehicles surrounding you. — Following the speed of the cars around you ignores the handbook's point that your speed should depend on road surface, weather, and other conditions, so the surrounding traffic may itself be going too fast for the situation.
- B. At the speed limit. — The handbook says that regardless of the posted speed limit your speed should depend on the conditions, so the limit alone is not always the safe speed.
Remember it
Think of the posted limit as a ceiling, not a target: the road and the weather set your actual speed.