"Which one do you think would do a better job in reducing global warming: the government, through laws intended to reduce the output of greenhouse gases, or businesses, through competition in the market system?"

Global Warming, a phenomenon, which has started showing its effects, needs to be countered soon. Increasing earth’s temperature, rising sea levels, change in the amount and pattern of precipitation, tsunami and earthquakes, are all after-effects of Global warming. I believe, the larger accountability lies with the Government rather than businesses. Government, through stricter laws can ensure lower emission of greenhouse gases. Also, by incorporating systematic plans to reduce pollution can help world diminish the effects of Global Warming.
Governments especially of developed and developing nations should prepare a 10-20 year plan of imposing stricter laws. This would also allow businesses to adapt within a time frame, and will help them remain competitive. Businesses cannot be hold responsible for reducing global warming, as their primary goal is to achieve sustainable growth and profits. Governments are socially elected and thus are more accountable such social concerns. Also, global warming being a worldwide phenomenon; can be handled only by joint efforts of all the nations. Businesses can only support these efforts in the long run.