Research Involving Family and Adoption Studies Has Demonstrated That

Research involving family and adoption studies has demonstrated that

A) the higher the percentage of shared genes between people,the higher their IQ correlations will be.
B) siblings reared together and cousins reared together have similar IQ correlations.
C) the correlations between the IQ scores of cousins reared together are very strong.
D) the correlations between the IQ scores of identical twins reared together are negative.