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
Widening of periodontal ligament is seen in: 
Select and explain. 
A. Hypercementosis, B. Osteosarcoma, C. Hypofunction of teeth, D. Paget's disease
B: Osteosarcoma
Answer: B: Osteosarcoma 
Explanation: Widening of periodontal ligament is seen in

Osteosarcoma
Chondrosarcoma
Scleroderma
Trauma from occlusion

Obliteration of periodontal ligament space is seen in

Hypercementosis
Ankylosis
Hypofunction of teeth
Paget's disease