The Earth's lithosphere

The Earth's atmosphere

The Earth's oceans

The Earth's biosphere

They react with ozone molecules to form chlorine monoxide and bromine monoxide.

They react with ozone molecules to form chlorine dioxide and bromine dioxide.

They react with ozone molecules to form chlorine trioxide and bromine trioxide.

They react with ozone molecules to form chlorine tetroxide and bromine tetroxide.

Volcanic eruptions release chlorine and bromine atoms into the atmosphere.

Volcanic eruptions release sulfur dioxide into the atmosphere.

Volcanic eruptions release carbon dioxide into the atmosphere.

Volcanic eruptions release methane into the atmosphere.

The Earth's crust releases chlorine and bromine atoms into the atmosphere.

The Earth's crust releases sulfur dioxide into the atmosphere.

The Earth's crust releases carbon dioxide into the atmosphere.

The Earth's crust releases methane into the atmosphere.

The Earth's mantle releases chlorine and bromine atoms into the atmosphere.

The Earth's mantle releases sulfur dioxide into the atmosphere.

The Earth's mantle releases carbon dioxide into the atmosphere.

The Earth's mantle releases methane into the atmosphere.

Increased ultraviolet radiation reaching the Earth's surface

Increased skin cancer rates

Increased eye cataracts

All of the above

An international treaty designed to protect the ozone layer

An international treaty designed to reduce greenhouse gas emissions

An international treaty designed to protect biodiversity

An international treaty designed to promote sustainable development

A ban on the production and consumption of ozone-depleting substances

A requirement to reduce the production and consumption of ozone-depleting substances

A requirement to develop and implement alternative technologies that do not use ozone-depleting substances

All of the above

It has led to a significant decrease in the production and consumption of ozone-depleting substances.

It has led to a significant decrease in the concentration of ozone-depleting substances in the atmosphere.

It has led to a significant decrease in the rate of ozone depletion.

All of the above

The high cost of alternative technologies

The lack of political will in some countries

The illegal trade in ozone-depleting substances

All of the above

It will continue to be updated and strengthened as needed.

It will eventually be replaced by a new treaty.

It will be phased out as the ozone layer recovers.

It is unclear what the future of the Montreal Protocol will be.

Reduce their use of products that contain ozone-depleting substances.

Support policies that promote the use of alternative technologies.

Educate themselves and others about the importance of protecting the ozone layer.

All of the above

The phase-out of chlorofluorocarbons (CFCs)

The development of alternative technologies that do not use ozone-depleting substances

The recovery of the ozone layer

All of the above

The illegal trade in ozone-depleting substances

The high cost of alternative technologies

The lack of political will in some countries

All of the above

It is unclear what the future of the fight against ozone depletion will be.

The fight against ozone depletion will continue until the ozone layer is fully recovered.

The fight against ozone depletion will eventually be won.

The fight against ozone depletion is already over.