Regard to the Findings of Many Longitudinal Studies on Attachment

regard to the findings of many longitudinal studies on attachment theory reported in the textbook, which statement accurately describes the overall conclusions?

A) The studies reported do not really test the heart of attachment theory, which is the claim that infant attachments form the basis for later relationships.
B) These longitudinal studies have provided a clear support for the link between parental separation and secure attachment.
C) Most of the studies relied on having people recall memories from childhood which was found to be an unreliable enterprise.
D) These longitudinal studies have provided mixed support for the predictions of attachment theory.