Whose research introduced 'The Strange Situation' to study attachment styles?

The correct answer is C, as Mary Ainsworth developed 'The Strange Situation,' a significant observational study designed to assess the types of attachment relationships that infants form with their caregivers. Conducted in the 1970s, this procedure involved observing infants' reactions to a series of planned separations and reunions with their primary caregivers. Ainsworth's work built upon the theoretical framework established by John Bowlby, who emphasized the importance of early relationships in child development.

Through 'The Strange Situation,' Ainsworth identified three primary attachment styles: secure, anxious-ambivalent, and avoidant, leading to a deeper understanding of how different attachment styles can affect a child's emotional and social development. This research has had a profound impact on the field of developmental psychology and childcare practices, influencing how caregivers and educators understand and respond to children's attachment needs.

The other individuals mentioned in the question, such as Knowles, Maslow, and Rogers, are primarily associated with different aspects of psychology and education, including adult learning theories, human motivation, and client-centered therapy, respectively, rather than attachment theory.