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: Gynaecology & Obstetrics
Which of the following surgical therapies is least effective in treatment of myoma associated with heavy menstrual bleeding 
Select and explain. 
A. Myomectomy, B. Hysteroscopic resection, C. Endometrial ablation, D. Hysterectomy
C: Endometrial ablation
Answer: C: Endometrial ablation 
Explanation: Endometrial ablation technique has high failure rate.