How can you recognize that a vehicle is about to change lanes?

Recognizing that a vehicle is about to change lanes is primarily indicated by the driver signaling or checking mirrors and blind spots. When a driver intends to change lanes, they typically use their turn signals to communicate their intention to other drivers and pedestrians. This signaling is crucial for maintaining safety on the road, as it alerts others to be cautious and allows for smoother traffic flow.

Additionally, a responsible driver will also check their mirrors and blind spots before making the lane change. This practice ensures that they are aware of any vehicles, cyclists, or pedestrians that might be in the way or not easily visible in their mirrors. By observing these actions, other drivers can accurately interpret the driver's intentions and prepare accordingly.

The other choices are not reliable indicators of an impending lane change. For instance, a driver merely looking forward and accelerating does not convey the intention to change lanes and may suggest different driving behavior. Similarly, a vehicle moving slower than the traffic can be a result of various factors unrelated to a lane change. Lastly, indicators being non-functional would make it impossible for other drivers to anticipate the lane change properly, highlighting the importance of functional signaling in safe driving practices.