Which of the following statements is NOT true of dopamine and schizophrenia?

A) Several lines of evidence have supported the original dopamine theory that symptoms of schizophrenia are caused by excess levels of dopamine in the frontal lobe and limbic system.
B) Phenothiazines and neuroleptics increase the functional level of dopamine, which helps to reduce psychotic symptoms of schizophrenia.
C) The traditional theory was proved too simple, and evidence supports that many people with schizophrenia do not respond to Phenothiazines, which may indicate that other neurotransmitters are involved in the disorder.
D) Critics of the original dopamine theory argue that the theory does not adequately explain the negative symptoms of schizophrenia.