The correct option is B To reduce global warming.
Kyoto protocol was signed in Kyoto, Japan in 1997. The goal of the protocol is to cut down the greenhouse gas emissions to the levels it was in 1990 to reduce global warming. The greenhouses gases were Carbon dioxide (CO2), Methane (CH4), Nitrous oxide (N2O), Hydrofluorocarbons (HFCs), Perfluorocarbons (PFCs) and Sulphur hexafluoride (SF6).