A nurse is assisting with the care of a school-age child who has respiratory failure due to pneumonia. Which of the following positions should the nurse encourage to allow maximal lung expansion?

A. Supine: This position can impair lung expansion and increase risk of aspiration or atelectasis. B. Side-lying: May improve comfort but does not optimize bilateral lung expansion. C. Upright: An upright or semi-Fowler's position maximizes chest expansion and oxygenation-the most effective for respiratory distress. D. Prone: Prone may be used in ICU settings for ARDS but is not first-line for general respiratory distress in children.