This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Lower Limb Traumatology, Subject name: Orthopaedics
Unna boot is used for treatment of: 
Select and explain. 
A. Diabetic foot ulcer, B. Varicose ulcers, C. Ankle instability, D. Calcaneum fracture
B: Varicose ulcers
Answer: B: Varicose ulcers 
Explanation: Unna boot is used for the varicose vein ulcers.