The nurse is providing discharge teaching to the parents of a 4-year-old with newly diagnosed asthma. An important tool to assess how well the asthma is controlled is:

Choice A reason: A peak expiratory flow meter is a device that measures how fast the child can exhale air from the lungs. It can help monitor the severity of asthma and the effectiveness of treatment. It can also help identify triggers and prevent asthma attacks.

Choice B reason: A metered dose inhaler with spacer is a device that delivers medication to the lungs. It can help relieve or prevent asthma symptoms, but it does not measure how well the asthma is controlled.

Choice C reason: Pulse oximetry is a device that measures the oxygen saturation of the blood. It can help detect hypoxia, which is a complication of asthma, but it does not measure how well the asthma is controlled.

Choice D reason: Inhaled steroids are a type of medication that reduce inflammation in the airways. They can help prevent asthma attacks and improve lung function, but they do not measure how well the asthma is controlled.

Choice A reason: This is not a valid basis for the nurse's response, as it implies that the child sleeps with the parents because of a lack of attention during the day. This may not be the case, and it may also offend the parents by questioning their parenting skills.

Choice B reason: This is a valid basis for the nurse's response, as it acknowledges the diversity and variability of family practices and preferences. It also shows respect and sensitivity for the parents' and the child's needs and comfort.

Choice C reason: This is not a valid basis for the nurse's response, as it is false and exaggerated. Sleeping with one's children is not illegal or abusive, unless there is evidence of harm or neglect. It may also alarm and anger the parents by accusing them of a crime.

Choice D reason: This is not a valid basis for the nurse's response, as it is based on a rigid and arbitrary developmental milestone. There is no fixed age for separating from parents, and it may vary depending on the child's temperament, attachment, and environment. It may also pressure and guilt the parents by implying that they are delaying their child's growth.