Which of the following are the four types of attachment identified by Ainsworth?

The classification of attachment styles, as identified by Mary Ainsworth in her research, includes secure attachment, anxious-avoidant attachment, anxious-resistant (also known as ambivalent) attachment, and disorganized attachment.

Secure attachment refers to children who feel comfortable exploring their environment and are readily comforted by their caregivers upon return after absence. Anxious-avoidant attachment describes children who avoid or ignore their caregivers, showing little emotion when the caregiver departs or returns. Anxious-resistant attachment, or ambivalent attachment, involves children who seek closeness to their caregiver but also show ambivalence, resisting comfort upon reunion because of anxiety about the caregiver's availability. Finally, disorganized attachment is characterized by a lack of clear attachment behavior; these children often appear confused or apprehensive and may display a mix of avoidant and resistant behaviors.

In this context, the inclusion of the specific correct types of attachment in your answer clarifies the categories established by Ainsworth and aligns with her findings in the Strange Situation procedure, where these four styles are notably observed and defined. The other choices incorrectly include terms that either do not correspond to Ainsworth's research or misrepresent the nature of attachment styles identified in her studies.