What is the hand signal used to indicate a slow or stop maneuver?

The hand signal used to indicate a slow or stop maneuver is when the left arm and hand are pointed downward. This gesture is a widely recognized signal among drivers and is part of standardized hand signals that help communicate intentions to other road users, especially when the vehicle's signals are not visible or functional.

Pointing the arm downward clearly indicates that the vehicle is slowing down or coming to a stop, making it clear to others on the road what the driver intends to do. This signal is essential for maintaining safety and ensuring other drivers and pedestrians are aware of the intended action.

Each of the other options represents different maneuvers: for instance, raising the left arm above the head signals a right turn, while extending the right arm straight out signals a left turn. Therefore, the signal indicating a slow or stop maneuver is specifically the left arm and hand pointed downward.