What is a possible long-term consequence of groundwater overdraft?
a. increased vegetation
b. unproductive wells
c. polluted groundwater
d. higher water tables

Groundwater overdraft is a phenomenon which happens when the use of groundwater is overly in excess the amount of recharge. This leads to the decline in groundwater level which in turn will lead to unproductive wells. Thus, the answer to this item is letter B. 

Answer the collision of tectonic plates;