Most freshwater use is
a. for irrigation
b. for industry and electrical power
c. to supply the public with drinking water
d. for swimming pools

Most freshwater use is - For industry and electrical power                    

The freshwater or running water is also used for irrigation and to supply people with water for everyday uses. But this is only about 30%.

So, the rest 70% of the fresh surface water is used in power plants to cool off machinery. This used water is again recycled and used or sometimes it is returned to its source.      

google my dude. if it doesn't show up ask me.

i believe it would cause an increase of percipitation, though i could be wrong. so i would say b is the answer.