Final answer:
The childhood attachment style where the child is distressed when the parent leaves, not comforted by a stranger, but quickly calms when the parent returns, is known as secure attachment. This attachment style is marked by a strong preference for the parent over strangers and a sense of safety and trust established through sensitive and responsive caregiving.
Step-by-step explanation:
When a child is distressed when a parent leaves, not comforted by a stranger, and quickly calms when the parent returns, the type of childhood attachment described is secure attachment. In a secure attachment, the child uses the parent as a secure base from which to explore their world. The parent's presence is preferred over a stranger, and upon reunion after a separation, the child will seek comfort from and is easily soothed by the parent. Secure attachment is associated with caregivers who are sensitive and responsive to their child's needs, which helps the child to develop trust and a sense of safety to explore their environment.
Conversely, with avoidant attachment, the child does not seek comfort from the parent upon their return and does not mind much when the parent leaves. In resistant attachment, the child may appear clingy and does not easily calm down upon the parent's return, often showing anger or resistance. Finally, disorganized attachment is characterized by erratic behaviors and is seen in children who may have faced abuse. These behaviors are not consistent with quickly calming upon a parent's return, which further supports the secure attachment classification for the described behavior.