This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
[{'content': 'According to Arnott grading system, both Ascending ramus and tuberosity is affected in: \nSelect and explain. \nA. Grade 1., B. Grade 2., C. Grade 3., D. Grade 4.', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Arnott grading\nI: Both side Ascending Ramus affected.\nII: Both Ascending Ramus + tuberosity\nIII: Entire maxilla + mandible', 'role': 'assistant'}]