Schizophrenia is marked by several unique brain traits, including: 

Enlarged ventricles 

Small/disorganized hippocampus

Small amygdala

The absence of a cerebellum would result in serious motor function deficits, but is absolutely not characteristic of the brains of patients with schizophrenia.

Many people with schizophrenia have hallucinations, which can be defined as sensory experiences without sensory stimulation. Although auditory, visual, tactile (touch), gustatory (taste), and olfactory (smell) hallucinations are all possible, auditory hallucinations, particularly hearing voices that no one else can hear, are by far the most common.

Schizophrenia has positive symptoms (characteristics that do not exist in neurotypical people) and negative symptoms (the lack of something that neurotypical people have). Therefore, hallucinations or delusions are a positive symptom, whereas flat affect (lack of facial expressions), apathy (lack of passion), avolition (lack of motivation), and monotone speech (lack of tone variance in speech) are all negative symptoms. 

Positive symptoms are characteristics that are in excess or beyond typical experience. Hallucinations and delusions are not typically experienced in daily life, while depression is a decreased ability to feel pleasure and asociality is defined as a decrease in social integration.

Negative symptoms are thoughts, feelings, or behaviors that are present in the average person but diminished in a person with a mental disorder. Diminished appetite is the only option that is not a negative symptom of schizophrenia.

Catatonia in individuals with schizophrenia causes limited reactivity to the environment and can include stereotyped behaviors such as repetitive movements or assuming bizarre poses for hours or even days. 

Schizophrenics experience psychosis through hallucinations and delusions. Hallucinations are defined as vivid sensations that seem real even though they are not. Hallucinations can occur in any of the five primary senses, although they are most commonly experienced through the auditory system. On the other hand, delusions are defined as false beliefs that persist despite evidence that indicates their falsity. There are multiple kinds of delusions, such as persecutory delusions, delusions of control (i.e. thought insertion), grandiose delusions, and referential delusions. In persecutory delusions, the victim believes others are continually persecuting him or her. Delusions of control, or thought insertions, are related to the belief that other people are controlling the victim. A victim beliefs other people putting thoughts into his or her head; therefore, controlling him or her. Grandiose delusions occur when a person thinks that he or she is significantly more important, great, and powerful than they really are. Last, referential delusions occur when people believe that external events have special meaning for them, and only them.

The correct answer is "paranoid schizophrenics have delusions of grandeur, while disorganized schizophrenics do not." Two of the other answers, of auditory hallucinations and a break between reality and a perception of reality, are tendencies and symptomatic of all forms of schizophrenia. Waxy flexibility is a characteristic of catatonic schizophrenia. A flat effect of emotions is seen in disorganized schizophrenia, not paranoid schizophrenia. 

It is incorrect that Schizophrenia impacts 10-20% of the population. Rather, depression has been found to impact 10-20% of the population. Schizophrenia is less common and impacts about 1% of the population. It is most commonly diagnosed in late adolescence and early adulthood. All of the other statements are correct. 

Schizophrenics do not have split personalities. Instead, schizophrenia refers to a break from reality rather than a mental break within the patient. In other words, patients experience a split from their thinking processes and emotional responses, not within their personalities. This differentiates schizophrenia from dissociative identity disorder. On the other hand, the flat affect, waxy flexibility, delusions, and making up words are all symptoms of schizophrenia.