Final answer:
The statement that air pollution can easily cross national boundaries is true. Air pollution consists of various pollutants from both natural and human activities, contributing to climate change, requiring global cooperation for effective management.
Step-by-step explanation:
Air pollution can indeed easily cross national boundaries, making the statement true. Pollutants such as soot, hydrocarbons, carbon monoxide, nitrogen, and sulfur oxides are part of air pollution, which is introduced into the atmosphere through various sources, both natural and human-caused. These can include dust storms, forest fires, volcanic eruptions, vehicular emissions, industrial processes, and more.
Air pollution varies by location and can impact global climate change, due to pollutants like carbon dioxide enhancing the natural greenhouse effect and raising Earth's surface temperature. The transport of pollutants across borders presents challenges in environmental protection efforts, as no single nation can effectively mitigate this pollution or the associated global warming without international cooperation.