Climate Scientist: The rising levels of methane in the atmosphere, which pose a significant threat to global climate stability, can only be mitigated by decreasing agricultural emissions. However, any nation that enforces stringent regulations on agricultural practices to achieve this reduction would likely face a decline in its agricultural output. No country will willingly incur the costs of such measures alone, as the benefits are global. Therefore, it is clear that the dire effects of increasing atmospheric methane will be inevitable unless _______. Which one of the following most logically completes the argument?