This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology and breast, Subject name: Surgery
Percentage of cold nodules that becomes malignant are 
Select and explain. 
A. 5%, B. 15%, C. 20%, D. 40%
C: 20%
Answer: C: 20% 
Explanation: 20% of 'cold' swellings and some 5% functioning or 'warm' swellings will be malignant.Ref: Bailey and Love, page no: 804