Answer:
a. Both Stefan's and Darnell's behaviors are common motor disturbances seen in schizophrenia
Step-by-step explanation:
Schizophrenia is a mental disorder where people are affected with the ability to feel, think and behave properly. People fails to respond to their thoughts and emotions.
In the context, both Stefan and Darnell are diagnosed with schizophrenia. Their symptoms are behaviors of motor disturbances where persons suffering from schizophrenia goes suffers. Stefan moves around the room rapidly and talks endlessly. While Darnell responds to nothing standing in one position. Thus these are the signs of motor disturbances which is seen in schizophrenia.