While waiting for EMS, which of the following should you actively monitor?

Monitoring the AB-CABS (Airway, Breathing, Circulation, Alertness, and Severe bleeding) is critical while waiting for Emergency Medical Services (EMS) because it focuses on the primary functions that sustain a victim's life. Ensuring that the airway is clear and open, checking for effective breathing, assessing circulation through pulse check, determining the victim's level of alertness, and looking for any severe bleeding are all fundamental steps in first aid care. Continuous monitoring of these vital signs is essential to detect any changes in the victim's condition, enabling the rescuer to take appropriate action if the situation deteriorates.

The other options, while important in specific contexts, do not prioritize the immediate life-saving concerns. For example, monitoring the victim's emotional state and the patience of onlookers may provide helpful information for the overall scene management, but they do not directly contribute to the victim's physiological needs. Similarly, paying attention to the surrounding environment is prudent for safety but is secondary to checking life-threatening conditions. Maintaining focus on AB-CABS directly ensures the best possible outcome for the victim until professional help arrives.