What does a sign with black lettering on a yellow background indicate?

• It warns drivers about potential hazards or changes in road conditions.
  Explanation:

  "Signs with black lettering on a yellow background are warning signs. They are used to alert drivers to potential hazards, road conditions, or upcoming changes to help ensure safe driving."
• It provides information related to construction zones and work areas.
• It indicates the presence of a school zone or a school crosswalk.
• It is used to show lane control instructions for drivers.