Agenda-21 was adopted in

Options

A. Kyoto protocol
B. Earth summit
C. Helsinki declaration
D. Montreal protocol

Answer

**Step-by-Step Solution:**

1. **Understanding Agenda 21**: Begin by recognizing what Agenda 21 is. It is a comprehensive plan of action to be taken globally, nationally, and locally by organizations of the United Nations System, governments, and major groups in every area in which human impacts on the environment.

2. **Context of Adoption**: Agenda 21 was adopted in the context of the Rio Declaration on Environment and Development. This declaration emphasizes the importance of sustainable development.

3. **Year of Adoption**: It is crucial to note the year when Agenda 21 was adopted, which is 1992.

4. **Location of Adoption**: The adoption took place during the United Nations Conference on Environment and Development, which is commonly referred to as the Earth Summit. This conference was held in Rio de Janeiro, Brazil.

5. **Identifying the Correct Option**: Given the options provided (Kyoto Protocol, Earth Summit, Helsinki Declaration, Montreal Protocol), the correct answer is the Earth Summit, as this is where Agenda 21 was officially adopted.

6. **Final Answer**: Therefore, the answer to the question "Agenda-21 was adopted in" is **Earth Summit**.

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