What could be an indication of a distracted driver?

Answer: A — Changing their speed erratically for no apparent reason

A distracted driver may exhibit erratic speed changes because their attention is divided, making it difficult for them to focus solely on the road. This distraction could stem from various factors, such as looking at their phone, engaging in conversation, or being otherwise preoccupied. When a driver alters their speed without a clear and sensible reason—like approaching a stoplight or a slower vehicle—it signals a lack of concentration. The other options reflect behaviors typically associated with attentive driving. Maintaining speed within legal limits, using turn signals correctly, and integrating smoothly into traffic indicate that a driver is likely focused and aware of their surroundings. Such consistent and appropriate actions suggest that a driver is paying attention to the road, unlike someone who is distracted and may inadvertently speed up or slow down unpredictably.