Which of the following clinical manifestations should the nurse ensure caregivers are able to identify as signs of worsening heart failure?

The correct answer is D because tachypnea and diaphoresis with feeding, poor weight gain, and irritability are indicative of worsening heart failure in infants. Tachypnea indicates respiratory distress, diaphoresis with feeding suggests increased effort to breathe, poor weight gain signifies inadequate cardiac output, and irritability may result from inadequate oxygenation. Bradycardia, rapid weight gain, and irritability (Option A) are not typical signs of worsening heart failure. Cough, edema, and increased work of breathing (Option B) are common heart failure symptoms but not specific to worsening condition. Abdominal pain, poor appetite, and cough (Option C) are not specific to worsening heart failure in infants.