TeXes Science Practice Test

Which statement correctly describes the environmental impact of increased carbon dioxide levels?

1. It only causes ocean acidification

2. It has no impact on climate

3. It can contribute to global warming

4. It primarily enhances plant photosynthesis

The correct answer is: It can contribute to global warming

The statement that increased carbon dioxide levels can contribute to global warming is correct because carbon dioxide (CO2) is a greenhouse gas. This means it has the ability to trap heat in the Earth's atmosphere, leading to an increase in global temperatures. As CO2 concentrations rise, the greenhouse effect becomes more pronounced, resulting in a warming of the planet. This warming can lead to a variety of environmental impacts, including changes in weather patterns, more intense storms, rising sea levels, and disruptions to ecosystems. The other statements do not accurately reflect the broader impacts of increased carbon dioxide levels. For example, while CO2 does contribute to ocean acidification, it is not the only impact, and asserting that it "only" causes this phenomenon limits the understanding of its overall effects. Saying it has no impact on climate is incorrect, as the scientific consensus affirms its significant role in climate change. Additionally, while CO2 can enhance plant photosynthesis to some extent, the overall consequences of increased levels of this gas are far more complex and involve many negative environmental effects. Therefore, the most comprehensive view reflects the connection between increased carbon dioxide levels and global warming.