A mother has brought her 2-week-old infant to the emergency department due to the baby's persistent and increasing jaundice. Blood testing reveals that the infant's unconjugated bilirubin level is 28 mg/dL and assessment does not reveal neurologic deficits. The infant's weight is normal and the mother claims to have had no significant difficulty feeding the infant. The most likely treatment for this infant will be: Answer A. phlebotomy. B. packed red blood cell transfusion. C. phototherapy. D. intravenous antibiotics.