What is LNG-20? Explain its mode of action.

Explanation

### Step-by-Step Solution:

1. **Definition of LNG-20**:
- LNG-20 stands for Levonorgestrel 20 mg, which is a type of intrauterine device (IUD) that releases the hormone Levonorgestrel. It is primarily used as a contraceptive method to prevent pregnancy.

2. **What is an Intrauterine Device (IUD)?**:
- An IUD is a T-shaped device that is inserted into the uterus. It is used for birth control and can be hormonal or non-hormonal. LNG-20 is a hormonal IUD.

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