The first graph shows carbon dioxide emission from fossil fuels between 1900 and 2008. Image courtesy of EPA The second graph shows the annual mean temperatures and the 5-year mean temperatures between 1880 and 2007. Image courtesy of NASA Which of the following conclusions are supported by these two graphs? A. As the amount of carbon dioxide increases, the average global temperatures decrease. B. Increased greenhouse gas emissions have no effect on global temperatures. C. As the average global temperatures decrease, the amount of carbon dioxide emissions decrease. D. Increased greenhouse gas emissions have an effect on global temperatures.