Answer:
Secure base; separation distress.
Explanation:
During this time, the secure base is measured. When Nikki leaves Stephanie all alone in the room, separation distress is measured. John Bowlby states that attachment is the connection between the baby and his caregivers. From their secure base, babies explore the world and come back to where their caregivers are. The separation distress is the distress babies feel when their caregivers disappear from their sight.