Which Statement About New Research into Biochemical Models for Mood

Which statement about new research into biochemical models for mood disorders is false?

A) The monoamine hypothesis needs to be updated with information that explains the slow onset of the clinical effects of the drugs.
B) PET scans and MRI can be used to discriminate between people with and without mood disorders in order to contribute to new models.
C) Animal models are no longer useful in the search for modern biochemical models for human conditions.
D) New models will have to consider multiple neurotransmitter systems and how they interact.