Which is a potential consequence of failing to check emissions adequately?

Failing to check emissions adequately can lead to a significant impact on public health and the environment. Vehicle emissions contain harmful pollutants, such as nitrogen oxides, carbon monoxide, and particulate matter, which can contribute to air quality deterioration. This deterioration is linked to various health issues, including respiratory problems, cardiovascular diseases, and other health conditions that affect the general population. Additionally, these emissions contribute to environmental issues such as climate change and global warming, which can have far-reaching effects on ecosystems.

The other options suggest positive outcomes related to vehicle performance, economy, or value, which do not align with the consequences of neglecting emissions checks. Instead, prioritizing emissions testing helps ensure that vehicles operate within regulatory standards, thereby protecting both public health and the environment.