According to Alexander Chess and Stella Thomas a child who expresses a low activity level is somewhat negative and is inflexible is a(n) child.?

According to Alexander Chess and Stella Thomas, a child who expresses a low activity level, is somewhat negative, and is inflexible is classified as a "slow-to-warm-up" child. This temperament type is characterized by a cautious approach to new experiences and a tendency to be less adaptable to change. Such children may take longer to adjust to new situations or environments compared to more easygoing peers.