Drivers are required to obey instructions from

• A. The signs posted along the road
• B. Other drivers
• C. Weather and road conditions
• D. Road signs, traffic signals, and police officers

Answer: (D)

Drivers must follow directions from official sources on the road, because these are the legally binding instructions that control right-of-way and safe operation. The best choice includes road signs, traffic signals, and police officers, covering all the typical ways authority is conveyed to drivers. Road signs tell you required actions like speed limits and stopping, traffic signals regulate flow at intersections, and police officers can direct traffic or override other signals when needed. This combination ensures you’re obeying the commands you’ll actually be held accountable for.

Relying on signs alone misses the active controls that signals and officers provide. Looking to other drivers isn’t reliable or safe as a basis for action, since you can’t predict or trust their choices. Weather and road conditions matter for caution and adjustments, but they don’t replace the explicit directions you must follow from signs, signals, or officers.