In child development, what term refers to the tendency of infants to react to the stimuli in their environment?

The term that refers to the tendency of infants to react to the stimuli in their environment is temperament. Temperament encompasses the innate characteristics and behavioral tendencies that influence how infants respond to various situations and stimuli, such as their level of activity, emotional intensity, and ability to adapt to change.

Temperament is critical in understanding early development because it can impact an infant's social interactions, learning styles, and even their later personality traits. For example, some infants may be more easily startled by sudden noises, while others might be more curious and explorative, reflecting different temperamental traits.

In contrast, attachment describes the emotional bond that develops between an infant and caregiver, focusing more on social relationships rather than innate reactions to stimuli. Development is a broader term that encompasses the process of growing and changing over time, including physical, cognitive, and social growth. Mood refers to a temporary emotional state, which is not specific to an infant's behavioral responses to environmental stimuli.