The Finding That Prenatal Viral Exposure, Rhesus Incompatibility, and Early

The finding that prenatal viral exposure, rhesus incompatibility, and early nutritional deficiency are associated with an increased risk of developing schizophrenia indicates that ________

A) genes do not play a role in vulnerability to schizophrenia.
B) anything that interferes with normal brain development might lead to a greater risk of schizophrenia.
C) environmental factors are more important than genetic factors when it comes to determining who is likely to develop schizophrenia.
D) the results of twin studies reflect the impact of a shared prenatal environment, not shared genes.