Contaminated Groundwater Cannot Cleanse Itself.Why

Multiple Choice

Contaminated groundwater cannot cleanse itself.Why?

A) Groundwater does not move at all and contaminants are not dispersed effectively.
B) Groundwater does not move at all and lower concentrations of dissolved oxygen exist for decomposition.
C) Contaminants are not dispersed effectively and lower concentrations of dissolved oxygen exist for decomposition.
D) Groundwater does not move at all and cold temperatures usually slow down reactions.
E) Contaminants are diluted easily,but not dispersed effectively.