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: Surgery
Brodie -Trendlenburg test demonstrates? 
Select and explain. 
A. Mid - thigh perforation, B. Deep vein thrombosis, C. Sapheno -- femoral incompetence, D. Calf perforators
C: Sapheno -- femoral incompetence
Answer: C: Sapheno -- femoral incompetence 
Explanation: Ans. is 'c' i.e., Sapheno-femoral incompetence