Acid rain is primarily caused by the emission of:

• Carbon dioxide

• Sulfur dioxide and nitrogen oxides

• Methane

• Chlorofluorocarbons (CFCs)

Which gas is primarily responsible for the greenhouse effect?

• Oxygen

• Carbon dioxide

• Nitrogen

• Hydrogen

Which of the following is a characteristic of a keystone species?

• It has a very large population size

• Its presence is crucial to maintaining the structure of an ecosystem

• It competes aggressively with other species for resources

• It is an invasive species

The "greenhouse effect" primarily occurs due to:

• Reflection of solar radiation by Earth's surface

• Absorption of infrared radiation by greenhouse gases

• The cooling effect of water vapor in the atmosphere

• Movement of warm air masses

Which of these is not a method of reducing carbon dioxide emissions?

• Afforestation (planting trees)

• Carbon capture and storage (CCS)

• Burning fossil fuels

• Renewable energy adoption

The term "biodiversity" refers to:

• The variety of species and ecosystems on Earth

• The number of people living in a particular area

• The diversity of geological formations

• The abundance of mineral resources

Which of the following pollutants is a result of incomplete combustion of fossil fuels?

• Carbon dioxide

• Carbon monoxide

• Nitrogen oxides

• Ozone

Which biome is characterized by low temperatures, permafrost, and a short growing season?

• Tropical rainforest

• Tundra

• Savanna

• Desert

Which of the following is an example of a renewable energy source?

• Coal

• Natural gas

• Wind

• Oil

What is the term for the gradual change in species composition in response to environmental conditions over time?

• Ecological succession

• Evolution

• Adaptation

• Speciation