Which of the following is a basic measure of first aid?

Ensuring an open airway and breathing is a fundamental aspect of first aid because it directly addresses two of the most critical functions of the body—respiration and circulation. In any emergency situation, the first priority is to assess whether a person can breathe effectively, as inadequate airflow can lead to a rapid deterioration of their condition. This measure is vital for preventing hypoxia (lack of oxygen) and ensuring that the brain and other essential organs receive the oxygen they need to function properly.

In first aid training, rescuers often focus on the ABCs: Airway, Breathing, and Circulation, with creating a clear airway being the first step. This clearly signifies the importance placed on maintaining life-supporting functions in acute medical situations. The other options involve actions that typically require a higher level of training, authority, or specific conditions—such as administering medications, performing surgeries, or providing rehabilitation—that are outside the scope of basic first aid.