What is a major consequence of groundwater contamination?

Groundwater contamination poses significant health risks and can adversely affect ecosystems, making this the correct choice. Contaminants such as heavy metals, bacteria, pesticides, and other pollutants can enter groundwater sources, leading to serious health issues for humans and animals who rely on this water for drinking or irrigation. For instance, drinking contaminated water can result in gastrointestinal illnesses, neurological disorders, and other serious health conditions. Additionally, when ecosystems are affected, it can disrupt the balance of local flora and fauna, leading to a decline in biodiversity and the health of the environment.

This option encompasses the far-reaching impacts of contamination beyond just water levels or well productivity. Unlike the other choices, which either imply a neutral or positive outcome from contamination, this answer highlights the crucial negative implications for public health and ecological integrity that arise from compromised groundwater quality.