Question

a peak flow reading in the green zone indicates that the patient
should seek medical attention immediately.
should continue with his current asthma action plan.
has a lung infection due to green mucus.
should increase use of his rescue inhaler.

Explanation:

In asthma management, peak flow zones are used. The green zone means the asthma is well - controlled. Seeking immediate medical attention (first option) is for worse zones (like red). A lung infection due to green mucus (third option) is incorrect as green zone doesn't relate to mucus - based infection. Increasing rescue inhaler use (fourth option) is for when control is lost (not green zone). So in green zone, continue current plan.

Answer:

should continue with his current asthma action plan.