Correct option is C
Hormone-releasing IUDs release small quantities of hormones that suppress endometrial changes and changes in the cervical mucus, cause ovulation and insufficient luteal activities. These Intra Uterine Devices are presently available as the non-medicated IUDs (e.g., Lippes loop), copper releasing IUDs (CuT, Cu7, Multiload 375) and the hormone releasing IUDs (Progestasert, LNG-20. Progestogens alone or in combination with estrogen can also be used by females as injections or implants under the skin.