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
According to Arnott grading system, both Ascending ramus and tuberosity is affected in: 
Select and explain. 
A. Grade 1., B. Grade 2., C. Grade 3., D. Grade 4.
B: Grade 2.
Answer: B: Grade 2. 
Explanation: Arnott grading
I: Both side Ascending Ramus affected.
II: Both Ascending Ramus + tuberosity
III: Entire maxilla + mandible