What is the major threat to the Ogallala aquifer? Too much extraction and not enough recharge

Too much extraction and not enough recharge

Too much recharge and not enough extraction
Too much recharge and not enough extraction

Farms switching crops that are raised and harvested
Farms switching crops that are raised and harvested

Installation of water conservation devices

the right option is; decreased genetic variation  

decreased genetic variation describes the effect of this environmental change.

genetic variation is the naturally occurring genetic diversities or differences between organisms of the same species in a population. genetic variation allows the survival and adaptability of a species when they encounter changing environmental conditions. when an endangered species reduces, it loses genetic variation which may not be restored even if the species rebound and will only be recovered through the gradual collection of mutations over many years.