Step 1: Understanding the Question:
This question tests knowledge of international environmental agreements.
Step 2: Detailed Explanation:
The Kyoto Protocol was adopted on December 11, 1997, in Kyoto, Japan.
It is an international treaty that commits developed countries to reduce greenhouse gas emissions.
It entered into force in 2005.
1996 (A), 1998 (C), and 1999 (D) are incorrect.
Thus, the correct year is 1997.
Step 3: Final Answer:
Thus, the Kyoto Protocol was adopted in 1997, which corresponds to option (B).
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