The boys end up being adopted by different families. After 20 years the boys are contacted by a researcher who is conducting a study on twins separated at birth and adopted by different families. John says that he finds it difficult to sustain relationships because he was not provided the support and care that he needed by his adopted mother as an infant. Which theory would best explain John's predicament

Attachment theory

Explanation:

The attachment theory teaches us that the relationship that exists between a child and his parents or caregiver has an effect on his development and latter relationship with others. It talks about an emotional bond with another person.

John's predicament is obviously explained by this theory because we have been told that he cannot sustain relationship because he did not have any form of attachment with his adopted mother.