Excessive water removal from the Central Valley Aquifer in California can lead to various environmental issues, but among the responses provided, the most relevant impact is:
It could cause faults to be less stable, resulting in earthquakes.
This is because excessive groundwater extraction can lead to land subsidence, which may affect the stability of geological faults, potentially triggering earthquakes. The other responses, while concerning in their own right, are less directly tied to the immediate consequences of aquifer depletion.