What item is required by law for a passenger when travelling on a motorcycle?

Answer: C — Helmet

The law mandates that all individuals riding as passengers on a motorcycle must wear a helmet. This requirement is in place because helmets significantly reduce the risk of head injuries in the event of an accident, enhancing overall safety for both the rider and the passenger. In many regions, including New Zealand, the use of helmets is strictly enforced, highlighting their importance for protecting against serious injury. While gloves, boots, and body armor can contribute to overall safety and are recommended for comfort and protection, the helmet remains the only legally required piece of protective gear for passengers.