Darryl Has Schizophrenia, Disorganized Type

Darryl has schizophrenia, disorganized type. He has visual hallucinations, and one day he saw a giant bug standing in front of him. He picked up a large knife and stabbed it. In reality, Darryl stabbed his mother who had come to tell him dinner was ready. His lawyer argues that Darryl cannot be found guilty because he had no idea what he was doing or that it was wrong. His lawyer is arguing the ________

A) M'Naghten rule.
B) Durham rule.
C) irresistible impulse rule.
D) American Law Institute standard.