Final answer:
The appropriate method of selecting an appropriately sized oropharyngeal airway (OPA) is to measure from the corner of the mouth to the earlobe. Using the patient's finger size as a guide or selecting the largest OPA available are not acceptable methods. Measuring from the nose to the chin is also not an accurate method.
Step-by-step explanation:
The appropriate method of selecting an appropriately sized oropharyngeal airway (OPA) is to measure from the corner of the mouth to the earlobe. This method ensures that the OPA is the correct size for the individual's anatomy and provides a clear airway.
Using the patient's finger size as a guide or selecting the largest OPA available are not acceptable methods because they do not take into account the individual's specific measurements. Measuring from the nose to the chin is also not an accurate method as it does not consider the width of the mouth.