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: Gynaecology & Obstetrics
Infra uterine copper T 200 is called copper 200 because : 
Select and explain. 
A. Cotain 200 mgs of copper, B. Has 200 sq. mm. of copper, C. Has 200 copper turns, D. Can be retained for 200 days
B: Has 200 sq. mm. of copper
Answer: B: Has 200 sq. mm. of copper 
Explanation: Has 200 sq. mm. of copper