A 3-year-old child with congestive heart failure resulting from an underlying congenital heart defect, is prescribed digoxin and furosemide. Which of the following assessment findings are MOST concerning?

A. A blood pressure of 100/56 and a small weight gain may indicate fluid retention, but they are not immediately life-threatening. B. A heart rate of 150 beats/minute with crying can be normal for a child of this age, especially during emotional distress. C. An apical pulse of 70 beats/minute and vomiting are concerning because they may indicate digoxin toxicity. A low heart rate (bradycardia) in a child on digoxin requires immediate attention. D. An hourly urine output of 45 mL/hour is adequate and not concerning in this context.