Answer: D) Don't have to.
Explanation for this question is being written.
Answer: B) Must not.
Answer: B) True
Answer: B) Must
Answer: A) Mustn't
Answer: D) Has to.
Answer: B) You musn't cheat in the GCSE.
Answer: B) In this situation "must" expresses an obligation.
Answer: A) Must
Answer: A) Not be able to.
Answer: C) Must
Answer: C) Mustn't
Answer: B) Mustn't
Answer: C) Don't need to.
Answer: C) You mustn't run in the hallway.
Answer: D) Mustn't
Answer: A) Obligation
Answer: B) In her class.
Answer: E) Don't have to.
Answer: D) Must
Answer: B) One must read the instructions.
Answer: C) You mustn't take the exam paper out of the classroom.
Answer: A) You mustn't take photographs at some sacred places.
Answer: A) Must not.