Final answer:
The symptom of schizophrenia related to diminished and inappropriate emotion, characterized by an emotionless state of apathy, is known as a 'flat affect'.
Step-by-step explanation:
Mandi, who was diagnosed with schizophrenia last year, exhibits a symptom related to diminished and inappropriate emotion. This symptom, where a patient lapses into an emotionless state of apparent apathy, is known as a flat affect. The correct answer to the student's question is: A. Flat affect. Schizophrenia can lead to various symptoms, including hallucinations, delusions, disorganized thinking, and negative symptoms such as flat affect, loss of pleasure, and loss of basic drives. Treatment often involves antipsychotic medications, which work by decreasing dopamine neurotransmission and can help manage symptoms, although they are not a complete cure.