What could be a sign of drowsy driving?

Answer: C — Yawning and heavy eyelids

Yawning and heavy eyelids are strong indicators of drowsy driving because they are common physiological responses to fatigue. When a driver feels tired, their body may signal the need for rest through yawning, which is often associated with a lack of alertness and the urge to sleep. Heavy eyelids indicate that the person is struggling to keep their eyes open, showing a clear decline in focus and attentiveness. These signs are critical to recognize because they suggest that the driver may not be able to react quickly or make sound decisions on the road, increasing the risk of an accident. Understanding these signs can help drivers recognize their own state of alertness and take necessary precautions, such as pulling over and resting, to ensure road safety.