A nurse is educating the parents of a 3-year-old child who has autism spectrum disorder (ASD). Which of the following patterns of behavior should the nurse include in the teaching? (Select all that apply.)

A. Fixation on certain items or topics is a common behavior in children with ASD, reflecting restricted interests and intense focus. B. Children with ASD generally resist frequent changes in routine; sudden changes can cause anxiety or distress. C. Self-harming behaviors, such as head-banging or biting, may occur in some children with ASD, often as a response to frustration, stress, or difficulty communicating needs. D. Behaviors in ASD are often repetitive and predictable, not spontaneous or highly unpredictable. E. Adhering to a rigid routine is characteristic of ASD, as it provides security and predictability in their environment. F. Children with ASD often engage in repetitive activities, so avoidance of repetition is not typical; repetitive behaviors are a core feature of the disorder.