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: ENT
For a mobile tumour on vocal cord, treatment is: 
Select and explain. 
A. Surgery, B. Chemotherapy, C. Radiotherapy, D. None of the above
C: Radiotherapy
Answer: C: Radiotherapy 
Explanation: According to Dhingra Radiotherpy is the treatment of choice for vocal cord cancer with normal mobility. Normal mobility of cord suggests that growth is only limited to the surface and belongs to either stage T1 or T2. TOC for stage T1 of glottic carcinoma - radiotherapy. TOC for stage T2 of glottic carcinoma - depends on mobility of the cord