Final answer:
The water problem in central California's vegetable basket is groundwater depletion, which occurs when pumping water from wells causes a localized drop in the water table. This can lead to a depletion of the groundwater and the need for deeper, more expensive wells. OPTION 2 IS CORRECT
Step-by-step explanation:
The water problem in the vegetable basket of the United States in central California is 2) groundwater depletion. As groundwater is pumped from water wells, there is a localized drop in the water table called a cone of depression.
When there are a large number of wells pumping water for a long time, the regional water table can drop significantly, leading to a depletion of the groundwater. This can force the drilling of deeper and more expensive wells that may encounter saline groundwater. OPTION 2 IS CORRECT