Which of the following strategies could countries use to cut their carbon emissions?

Which of the following strategies could countries use to cut their carbon emissions?

A. increased energy efficiency of existing infrastructure and appliances

B.greater vehicle efficiency e.g. increased miles per gallon, and a shift to electric cars

C. increased use of renewable sources of electricity such as solar or wind power

D. geologic disposal of carbon dioxide by capturing emissions and pumping them into spaces in rock deep underground

E. all of the above and more!