Bachelor of General Studies (BGS) Degree Practice Exam

Which statement accurately describes global warming?

1. The Earth has cooled significantly over the last century

2. Burning fossil fuels is the leading contributor of global warming

3. The temperature of the ocean has remained stable

4. Greenhouse gas levels have decreased since the Industrial Revolution

The correct answer is: Burning fossil fuels is the leading contributor of global warming

The statement that burning fossil fuels is the leading contributor of global warming is accurate due to the significant role that fossil fuel combustion plays in increasing greenhouse gas concentrations in the atmosphere. When fossil fuels such as coal, oil, and natural gas are burned for energy, they release carbon dioxide and other greenhouse gases. These gases trap heat in the atmosphere, leading to an overall increase in global temperatures. This mechanism is a fundamental aspect of climate science, clearly showing the direct correlation between human activities, particularly industrial and energy production processes, and the enhancement of the greenhouse effect. In contrast, the other statements do not align with established scientific understanding. The Earth has not significantly cooled but rather warmed over the past century. The oceans have also experienced noticeable temperature increases, affected by global warming, as they absorb much of the excess heat and carbon dioxide. Finally, greenhouse gas levels have significantly increased, not decreased, since the Industrial Revolution, largely due to industrial activities and deforestation, further supporting the accuracy of the correct statement regarding fossil fuels.