What did Harry Harlow demonstrate in his classic study of attachment among baby monkeys?

• A. That social isolation has no effect on the emotional development of baby monkeys.
• B. That infant monkeys preferred comfort and contact from a soft surrogate mother over food provided by a wire mother.
• C. That attachment in monkeys is solely based on the provision of food by the caregiver.
• D. That baby monkeys do not form attachments to surrogate mothers in the absence of their biological mothers.

Answer: (B)

Verified step by step guidance

1. Understand the context of Harry Harlow's study, which focused on attachment behaviors in infant monkeys and how these behaviors relate to emotional development.
2. Recognize that Harlow used surrogate mothers made of wire and cloth to test whether infant monkeys preferred the mother who provided food or the one who provided comfort.
3. Note that the key variable in the experiment was the type of surrogate mother: one that provided nourishment (wire mother) and one that provided tactile comfort (cloth mother).
4. Observe the behavior of the infant monkeys, specifically which surrogate mother they spent more time with and sought comfort from when frightened or stressed.
5. Conclude that Harlow demonstrated that attachment is not solely based on food provision, but rather on the need for comfort and contact, as infant monkeys preferred the soft, comforting surrogate mother over the wire mother that provided food.