To solve this problem, we need to identify which of the given options is a hormone-releasing intrauterine device (IUD). Let's analyze each option:$\newline \bullet$Option 1: Multiload 375$\newline$ - Multiload 375 is a type of copper IUD. It releases copper ions, which are toxic to sperm, but it does not release hormones.$\newline \bullet$Option 2: LNG-20$\newline$ - LNG-20 is a hormone-releasing IUD. It releases levonorgestrel, a type of progestin hormone, which helps in preventing pregnancy.$\newline \bullet$Option 3: Cervical cap$\newline$ - A cervical cap is a barrier method of contraception. It is a small cup made of silicone that fits over the cervix to block sperm from entering the uterus. It does not release hormones.$\newline \bullet$Option 4: Vault$\newline$ - The term "vault" does not refer to any known contraceptive device. It is not related to hormone-releasing IUDs.$\newline$Based on the analysis, the correct answer is Option 2: LNG-20, which is a hormone-releasing intrauterine device.