A nurse is monitoring a 6-month-old infant 20 min after administering a hepatitis B immunization. Which of the following findings is the nurse's priority?

A. Redness at the injection site is a common and mild reaction to vaccines. It does not typically require immediate medical intervention unless it worsens or is accompanied by more severe symptoms. B. A temperature of 37.7° C (99.9° F) is a low-grade fever, which is a common, expected response after immunization. It is not a priority unless it increases significantly or is accompanied by other concerning symptoms. C. Prolonged crying can sometimes occur after immunizations, but it is usually self-limited and resolves within a short period. If the crying is not excessive and does not indicate distress, it is generally not a priority concern. D. Hives on the child’s neck could be a sign of an allergic reaction, such as anaphylaxis, which is a medical emergency. The nurse should immediately assess the child’s airway and provide necessary interventions, such as administering epinephrine, if required. This finding is the priority because it suggests a possible severe allergic response