A school-age client with asthma has been monitoring their daily peak expiratory flow rates(PEFR). The client's mother calls the clinic to report that the PEFR was at 45% of their personal best. Which guidance should the nurse provide to the mother?

"Your child needs to go to the hospital as soon as possible."

"Have your child use their inhaled corticosteroid and follow it with albuterol."

"Your child needs to administer salmeterol right away."

"Continue to watch the PEFR readings and call back if they go below 40%."