All of the following pollutants were targeted for reduction by 2010, according to The 1999 Protocol, except ________.
nitrous oxide sulfur dioxide ammonia CFCs VOCs
The 1999 Protocol, also known as the Gothenburg Protocol, primarily targeted reductions in sulfur dioxide, nitrogen oxides, volatile organic compounds (VOCs), and ammonia. However, it did not specifically target the reduction of CFCs (chlorofluorocarbons), as these substances were primarily addressed under the Montreal Protocol, which focused on ozone-depleting substances.
Therefore, the correct answer is CFCs.