Which of the following is NOT a sign of respiratory distress in a newborn?

Bradycardia, which refers to a slower than normal heart rate, is not typically considered a direct sign of respiratory distress in a newborn. Instead, respiratory distress is characterized primarily by signs related to the respiratory system itself.

Grunting is a method newborns use to increase end-expiratory pressure and is suggestive of distress. Cyanosis indicates inadequate oxygenation and is a critical sign that requires immediate attention. Flaring nostrils can indicate increased work of breathing as the infant attempts to receive more air, often in response to respiratory distress. These signs are specifically related to difficulty in breathing or insufficient oxygen levels.

Therefore, while bradycardia can occur in situations where an infant is in distress (including respiratory distress), it is not a respiratory sign and thus is the correct answer to identify what does not belong in this context of signs associated with respiratory distress.