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: Surgery
Post operative radiotherapy in breast is given for- 
Select and explain. 
A. To prevent metastasis, B. Ablation of remnant of cancer tissue, C. To prevent recurrence, D. Prevents distal metastasis
C: To prevent recurrence
Answer: C: To prevent recurrence 
Explanation: None