A nurse is caring for a child who is having a tonic-clonic seizure and vomiting. Which of the following actions is the nurse's priority?

A. Timing the seizure is important for documentation and determining severity, but it is not the first priority in this situation. B. Removing eyeglasses can help prevent injury, but it is not the most urgent action during active vomiting. C. Placing a pillow may prevent head injury, but during a seizure, this may not be safe or effective, especially if vomiting is present. D. The priority during a seizure with vomiting is to turn the child to a side-lying position to maintain an open airway and prevent aspiration. This is the most immediate and critical intervention.