Correct Response: D. Children who regulate emotional responses to frustration and are able to refocus on another activity demonstrate an internal ability to self-regulate, which is a cornerstone of early childhood development. Although working with a variety of materials (A) is reflected in this child's behavior, it does not demonstrate an internal ability. Identifying learning strengths (B) is an aspect of assessment and is not an internal ability of the child. Persisting with a task under pressure (C) is not demonstrated here because there is no pressure noted in the given situation.