This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Surgery
Risk factors for malignant change in an asymptomatic patient with a gall bladder polyp on ultrasound include all of the following except 
Select and explain. 
A. Age > 60 years, B. Rapid increase in size of polyp, C. Size of polyp > 5 mm, D. Associated Gall stones
C: Size of polyp > 5 mm
Answer: C: Size of polyp > 5 mm 
Explanation: Gall bladder polyp more than 10 mm in size needs surgical intervention as the risk for developing malignancy is greater.Other risk factors include age>60 yrs,association with gallstones,rapid increase in size of polyp,symptomatic,sessile polyp. Reference:SRB's manual of surgery,5th edition,page no:658.