This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Contraceptives, Subject name: Gynaecology & Obstetrics
Which of the following is a frameless IUD: 
Select and explain. 
A. Mirena, B. Cu Fix, C. Cu T 380A, D. Multiload 375
B: Cu Fix
Answer: B: Cu Fix 
Explanation: Newer IUDs Cu-Fix IUD (Flexi-Gard): Frameless IUD consisting of six copper sleeves (300 mm2 of copper) strung on a surgical polypropylene nylon thread, which is knotted at the upper end. Cu Safe IUD: Device has a T-shaped radio-opaque plastic body. The ends of the flexible transverse arms are inwardly bent, providing a nonirritating, fundus-seeking mechanism.