The goal of the Montreal Protocol is aimed at restoring what?

The Montreal Protocol focuses specifically on the restoration of stratospheric ozone. This international treaty was established to phase out the production and consumption of substances that deplete the ozone layer, particularly chlorofluorocarbons (CFCs) and halons. The stratospheric ozone layer serves a critical function by absorbing the majority of the sun's harmful ultraviolet (UV) radiation. The depletion of this layer has significant environmental and health implications, leading to increased rates of skin cancer, cataracts, and adverse effects on ecosystems.

By targeting the substances that harm the ozone layer, the Montreal Protocol has been successful in promoting recovery of ozone levels and has seen notable positive results in restoring the stratospheric ozone. This recovery is an essential step toward protecting the Earth's climate system and public health, aligning it with the treaty's objectives. Thus, the correct answer emphasizes the protocol’s commitment to ozone restoration rather than addressing carbon emissions or greenhouse gases directly, which are not its primary focus.