When the newborn's crib was moved suddenly, the nurse noticed that his legs flexed and arms fanned out, and then both came back toward the midline. How would the nurse interpret this behavior?

A. The grasp reflex: The grasp reflex involves the newborn curling their fingers around an object placed in the palm, not the rapid extension and abduction of arms and legs. It does not explain the described startle response. B. The Moro reflex: The Moro reflex, or startle reflex, is a normal neonatal reflex in which the infant extends and abducts the arms and legs, then brings them back toward the midline in response to sudden movement or a loud noise. It indicates intact neurologic function and typically disappears by 4–6 months of age. C. A neurological abnormality: This behavior is expected in healthy newborns and represents normal neurologic function, not a pathologic condition. D. An abnormality of the musculoskeletal system: The described response is a reflex mediated by the nervous system, not a musculoskeletal defect. No structural abnormality is indicated by this behavior.