A lifeguard responding to an emergency reflects which duty?

The correct choice highlights the critical responsibility of a lifeguard in emergency situations, which is the duty to act. This duty encompasses the actions a lifeguard must take to provide aid, ensure safety, and manage emergencies effectively. In instances where a situation escalates, such as a swimmer in distress, it is imperative for a lifeguard to respond promptly and appropriately to help mitigate the emergency and provide necessary assistance, adhering to the protocols they have been trained in.

The duty to act is fundamental because it is not just about being present or observing the environment; it requires the lifeguard to engage actively in a potentially life-saving role. This encompassing duty includes recognizing the emergency, applying the knowledge and skills acquired through training, and performing the necessary interventions that could mean the difference between life and death.