Which reflex is characterized by an infant spreading their arms and fingers in response to being startled?

The Moro reflex, also known as the startle reflex, is characterized by an infant's response to a sudden stimulus, such as a loud noise or a feeling of falling. When startled, infants will instinctively open their arms and spread their fingers, often accompanied by a brief cry or facial expression of fear or surprise. This reflex serves as a protective mechanism for infants, indicating their development and neurological function.

The Moro reflex typically manifests in the first few months of life and begins to diminish around six months as the child's neurological system matures. Understanding this reflex is vital for healthcare providers as it offers insight into the infant's neurological status and development, allowing for early detection of potential issues.

The other options relate to different reflexes that serve distinct functions; for instance, the rooting reflex helps infants locate food and the grasp reflex involves their ability to grip objects placed in their palms.