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: Radiology
A radiolucency in bone without periosteal bone reaction is seen in 
Select and explain. 
A. Squamous cell carcinoma, B. Garres osteomyelitis, C. Osteosarcoma, D. Chronic osteomyelitis
A: Squamous cell carcinoma
Answer: A: Squamous cell carcinoma 
Explanation: Any lesion of bone destruction that has ill-defined borders and a lack of peripheral bone response (sclerosis) should be viewed with suspicion.
Squamous cell carcinoma originating in bone 
The internal structure is wholly radiolucent with no evidence of bone production and very little residual bone left within the center of the lesion.
Periapical image reveals bone destruction similar to periodontal disease around the lateral incisor from a squamous cell carcinoma originating in the soft tissues of the alveolar process. In image A note the lack of a sclerotic bone reaction at the periphery.