How does groundwater become polluted?

a
Pollutants mixed with water pass through permeable layers above the aquifer.
b
Refuse infiltrates the water table when garbage is dumped.
c
Factories dump their waste directly into aquifers.
d
All of the above

I would say d, all of the above.

All of the above is the right answer

a social contract.

"a social contract is an agreement between citizens and their leader where the citizens give up certain freedoms in exchange for protection. the constitution of the united states is an example of a social contract."