Research on the Causes of Schizophrenia Strongly Suggests That

Research on the causes of schizophrenia strongly suggests that

A) there is a genetic predisposition to schizophrenia.
B) almost anybody will develop schizophrenia if exposed to extensive environmental stress.
C) schizophrenia patients suffer from a deficiency of the neurotransmitter serotonin.
D) if adopted children's adoptive parents have schizophrenia,they will,too.