The nurse is sitting with a client diagnosed with schizophrenia, who starts to laugh uncontrollably, although the nurse has not said anything funny. The nurse should say:

Choice A Reason
Hyperreflexia refers to an overactive or overresponsive reflexes, which is a neurological condition and not directly related to the behaviors described. It is typically seen in conditions affecting the central nervous system and is not characterized by the inability to wait turns or interrupting conversations.

Choice B Reason
Defiance implies a conscious choice to resist authority or rules, which may not necessarily be the case here. While children with behavioral issues may exhibit defiant behaviors, the symptoms described are more indicative of a lack of impulse control rather than a deliberate choice to defy.

Choice C Reason
Inattention is a component of several behavioral and cognitive disorders, including ADHD. However, the behaviors described—blurting out answers, inability to wait for turns, and interrupting others—are more specifically associated with impulsivity rather than inattention alone.

Choice D Reason
Impulsivity is the tendency to act on a whim, displaying behavior characterized by little or no forethought, reflection, or consideration of the consequences. The behaviors described—such as blurting out answers and interrupting others—are classic signs of impulsivity, which is often seen in conditions like ADHD.

Choice A reason:
A respiratory rate of 24/min is slightly elevated, which can be expected in a client with pneumonia due to the body's attempt to increase oxygen intake and carbon dioxide elimination. However, this rate does not directly indicate ineffective airway clearance.

Choice B reason:
A weak, nonproductive cough is a key indicator of ineffective airway clearance. In pneumonia, the presence of secretions in the airways is common, and an effective cough is necessary to clear these secretions. A weak cough that does not produce sputum suggests that the client is unable to clear their airways effectively, which can lead to impaired gas exchange and worsening of symptoms.

Choice C reason:
Pulse oximetry (SpO2) of 90% indicates that the client's oxygen saturation is below the normal range, which is typically between 95-100% for healthy individuals. While this finding is concerning and warrants intervention, it is a result of ineffective airway clearance rather than a direct indicator of it.

Choice D reason:
Shortness of breath with activity is common in clients with pneumonia and can result from various factors, including impaired gas exchange, decreased lung compliance, and increased work of breathing. While it may be associated with ineffective airway clearance, it is not as specific as a weak, nonproductive cough for indicating this particular problem.