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
What is present in the part of the bone which received radiotherapy - 
Select and explain. 
A. Response to radiotherapy is good, B. Fast healing, C. More destruction of bone, D. Tumour regression is not affected
C: More destruction of bone
Answer: C: More destruction of bone 
Explanation: Infection and radiation, both cause bone destruction and predispose to pathological fracture.