Which hand signal indicates a driver is about to make a right turn?

The hand signal indicating that a driver is about to make a right turn is achieved by pointing the arm straight up. This signal is universally recognized and serves as a means of communicating intentions to other road users when the vehicle's turn signals may not be visible or operational. By using this signal, the driver effectively conveys the intent to turn right, ensuring the safety of themselves and others on the road.

The other signals serve different purposes: extending the arm straight out indicates a left turn, while pointing the arm straight down is a signal to stop or slow down. Both arms raised is not a standard signal for any driving maneuver, which emphasizes why the upward-pointing signal is the correct choice for a right turn.