Final answer:
The head-tilt/chin-lift is the recommended maneuver for opening the airway of an unconscious patient.
Step-by-step explanation:
The correct answer to the question is B. the recommended maneuver. The head-tilt/chin-lift maneuver is a technique used to open the airway of an unconscious patient and is commonly recommended in first aid and CPR training.
This maneuver involves gently tilting the patient's head back with one hand while lifting their chin with the other hand. This helps to align the airway and open it up, allowing for better breathing.
It is important to note that the head-tilt/chin-lift maneuver should only be performed in the absence of cervical spine trauma, as it could potentially worsen any existing neck injuries.