Global agreement to reduce the levels of ODS was done is

Options

A. Vienna Convention
B. Rio de Janeiro Conference
C. Kyoto Protocol
D. Montreal Protocol

Answer

**Step-by-Step Solution:**

1. **Understanding Ozone Depleting Substances (ODS):**
- Ozone Depleting Substances (ODS) are chemicals that contribute to the depletion of the ozone layer. A common example of ODS is Chlorofluorocarbons (CFCs).

2. **Recognizing the Importance of the Ozone Layer:**
- The ozone layer is crucial as it acts as a shield against harmful ultraviolet (UV) radiation from the sun. This radiation can cause serious health issues, including skin cancer and eye problems.

3. **Identifying the Need for Global Action:**
- Due to the harmful effects of ODS on the ozone layer and the subsequent risks to human health and the environment, there was a need for international cooperation to address this issue.

4. **Identifying the Global Agreement:**
- The global agreement aimed at reducing the levels of ODS is known as the **Montreal Protocol**. This protocol was signed in **1987** in Montreal, Canada, and became effective in **1989**.

5. **Purpose of the Montreal Protocol:**
- The primary purpose of the Montreal Protocol is to reduce the emission of ozone-depleting substances to protect the ozone layer.

**Final Answer:**
The global agreement to reduce the levels of Ozone Depleting Substances (ODS) is the **Montreal Protocol**.

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