Match column I with column II, and choose the correct combination from the options given below.

Column I	Column II
a. Non-medicated IUD	1. Vaults
b. Copper releasing IUD	2. Lippes loop
c. Hormone releasing IUD	3. Multiload 375
d. Barrier	4. LNG-20

The correct option is C a-2, b-3, c-4, d-1
Non-medicated IUD- Lippes loop Non-medicated IUDs work by immunomodulating the environment of the uterus. It initiates a sterile inflammatory response in the uterus which stimulates accumulation of macrophages. This results in the phagocytosis of the sperms. Examples include Lippes loop.

Copper releasing IUD- Multiload $375$ Copper releasing IUDs releases copper ions in the uterus which suppress the motility and fertilising ability of sperms and prevent fertilisation. Examples include CuT, Cu7, Multiload $375$.

Hormone releasing IUD- LNG$-20$ Hormone-releasing IUDs release hormones such as progesterone in the uterus which make the cervix hostile by making the mucus thick and sticky due to which sperm are not able to reach the uterus. Besides, it makes the uterus unsuitable for allowing implantation. Examples include LNG$-20$ and progestasert.

Barrier contraceptive methods- Vaults Barrier contraceptive methods prevent the physical meeting of sperm and ovum. Examples include condoms, diaphragms, cervical caps etc. Vault is a barrier used by the females to cover their cervix during coitus to prevent fertilisation.