The Concordance Rate for Affective Disorder for Monozygotic Twins

The concordance rate for affective disorder for monozygotic twins

A) is identical to that of dizygotic twins.
B) is the same whether or not the twins were raised in the same household.
C) proves that affective disorder is mostly an effect of the environment.
D) is higher than that for dizygotic twins.
E) is less than that noted for close relatives suffering from affective disorder.