WILL GIVE BRAINLIEST

Read this excerpt from We Beat the Street.

"You’re just plain lazy! You think this is hard? Wait until you’re pulling twenty-four-hour shifts as a resident in a hospital. Wait until you hold someone’s life in your hands and that person is depending on YOU to have the skill and knowledge to save his life.” She whipped back into her lecturing voice. "Strict personal discipline and adherence to rules are absolutely necessary for a doctor’s success!” She glared at him.
"I’m not lazy,” Rameck replied sullenly. "I’m just not used to all this discipline.”
"Get used to it!” Carla snapped back at him. "You’re one of the brightest young men I’ve ever met! Discipline won’t kill you. Carelessness will.”

Why does the author include this exchange?

A. to reveal the cruelty of the instructors
B. to illustrate Carla’s high expectations
C. to show the accomplishments of the students
D. to suggest Rameck’s disrespect of authority