This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Schizophrenia and other psychotic disorders, Subject name: Psychiatry
The most commonly implicated neurotransmitter in the aetiology of schizophrenia is 
Select and explain. 
A. Norepinephrine, B. Serotonin, C. Dopamine, D. GABA
C: Dopamine
Answer: C: Dopamine 
Explanation: Schizophrenia is presently thought to be probably due to a functional increase of dopamine at the postsynaptic receptor, though other neurotransmitters such as serotonin (especially 5-HT2 receptors), GABA and acetylcholine are also presumably involved. Ref: A Sho Textbook of Psychiatry, Niraj Ahuja, 7th Edition, pg. no. 63