The correct answer is option 2, which consists of statements 1 and 3. Statement 1 is correct because the Kyoto Protocol, an international treaty that commits state parties to reduce greenhouse gas emissions, did indeed come into force in 2005.

Statement 2 is incorrect. The Kyoto Protocol does not primarily deal with the depletion of the Ozone layer. Instead, it primarily focuses on reducing greenhouse gas emissions that contribute to global warming. Ozone depletion is mainly addressed by the Montreal Protocol.

Statement 3 is correct. Methane is considered a more harmful greenhouse gas than carbon dioxide. Although both gases contribute to global warming, methane is estimated to be 28-36 times more effective than carbon dioxide at trapping heat in the atmosphere over a 100-year period. Therefore, statements 1 and 3 are correct, making option 2 the right answer.