A mother brings her 3-week-old infant to the clinic because the baby vomits after eating and always seems hungry. Further assessment indicates that the infant's vomiting is projectile, and the child seems listless. Which additional assessment finding indicates the possibility of a life-threatening complication?
Correct Answer: D
Rationale: Crying without tears is a sign of severe dehydration, which is a potentially life-threatening complication in infants with projectile vomiting. Dehydration can rapidly progress in infants, leading to serious consequences if not promptly addressed. The combination of projectile vomiting, listlessness, and absence of tears when crying should raise concerns about severe dehydration and the need for urgent intervention to prevent further complications.