This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Venous Disorders, Subject name: Surgery
Varicose veins of size less than __can be best treated by sclerotherapy: 
Select and explain. 
A. 2 mm, B. 3 mm, C. 4 mm, D. 6 mm
B: 3 mm
Answer: B: 3 mm 
Explanation: Sclerotherapy is useful for dealing with minor varicosities (<3 mm) and recurrences in the calf and lower leg. Amount of sclerosants used in treatment of varicose veins is 0.5 ml.