Final answer:
The concerned attendee should be advised to administer the bronchodilator (rescue inhaler) first during an asthma attack, as it provides immediate relief by expanding the air passages, which is crucial in an emergency situation.
Step-by-step explanation:
The most appropriate advice for the concerned attendee regarding her granddaughter's asthma is to administer the bronchodilator (rescue inhaler) first in case of an asthma attack. Bronchodilators are short-term, fast-acting drugs that are used to relieve the symptoms of an asthma attack by soothing the constricted air passages and helping to re-expand them, making breathing easier. These medications usually start to take effect almost immediately. In contrast, corticosteroids are used for long-term control and prevention of asthma attacks and are not ideal for immediate relief during an acute asthma episode. While it is always advisable to consult a physician, during an emergency situation involving an asthma attack, promptly using the bronchodilator can be life-saving and should not be delayed by waiting for medical advice.