It Is Especially Important to Protect Groundwater Within Cave Systems

It is especially important to protect groundwater within cave systems from contamination because:

A) water is not filtered, and there is not enough time for microorganisms to consume contaminants.
B) karst groundwater often seeps upward into the soil and contaminates agricultural crops.
C) the chemical constituents of limestone tend to enhance contaminants rather than degrade them.
D) pollutants accumulate so rapidly that natural cleaning mechanisms are overloaded.