Kyoto Protocol was endorsed at:

Options

A. CoP - 6
B. CoP - 4
C. CoP - 3
D. CoP - 5

Explanation

**Step-by-Step Solution:**

1. **Understanding the Kyoto Protocol**: The Kyoto Protocol is an international treaty aimed at reducing greenhouse gas emissions. It was created to combat global warming and its associated environmental issues.

2. **Identifying the Conference of Parties (COP)**: The Kyoto Protocol was established during a specific session of the Conference of Parties (COP), which is a gathering of countries that are parties to the United Nations Framework Convention on Climate Change (UNFCCC).

3. **Finding the Correct Session**: The Kyoto Protocol was endorsed at the third session of the COP. This session is referred to as COP 3.

4. **Location and Date**: The COP 3 session took place in Kyoto, Japan, in 1997. This is significant because the protocol derives its name from the city where it was adopted.

5. **Eliminating Incorrect Options**: The question presents options including COP 4, COP 5, and COP 6. Since the Kyoto Protocol was specifically adopted at COP 3, these options can be eliminated as incorrect.

6. **Final Answer**: Therefore, the correct answer to the question "Kyoto Protocol was endorsed at:" is COP 3.

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