The complex interaction of biological, psychological, and social factors in human development is best explained by the Systems theory. Other theories like Developmental, Psychosocial crisis, and Existential psychology do not encompass this complexity. Therefore, Systems theory is the correct answer. ;
The interaction of biological, psychological, and social factors in human development is best described by Systems theory. This theory highlights the interconnectedness of various influences on growth and behavior. Therefore, the correct answer is C. Systems.
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