Which of the Following Six-Year-Old Children Would Be Most Likely

Which of the following six-year-old children would be most likely to experience an increase in IQ over the next few years?

A) Darius, who continues living with his loving middle-class biological parents
B) Aron, who continues living in an understaffed orphanage
C) Ceili, who was recently adopted from an understaffed orphanage by loving middle-class parents
D) Bettina, who recently started living in an understaffed orphanage following the death of her parents