Which of the following is the best example of a toddler using a caregiver as a secure base?

In this scenario, Kristina's reluctance to leave her mother's side indicates anxiety rather than a secure base relationship. While she is attached to her mother, her fear of exploring without her does not demonstrate healthy use of a secure base, as she is not engaging with her surroundings.

Celia’s initial distress shows some attachment but does not exemplify the secure base concept. Her eventual adaptation and play indicate resilience, yet it reflects her ability to adjust rather than using her caregiver as a source of support during exploration.

Nina’s indifference to her mother's return suggests a lack of attachment or secure base behavior. Instead of seeking comfort or reassurance, her behavior indicates an emotional distance, which does not align with the secure base concept.

Paz's inconsolable crying when her mother returns suggests distress upon separation but does not demonstrate the secure base behavior. This reaction indicates an anxious attachment style rather than the healthy exploration characteristic of a secure base relationship.