Early irrigation systems brought river water to forests. mountains. oceans. fields.

Irrigation is the process of providing water to land that would otherwise be too dry to cultivate cops on it, turthing this land into a fertile  field.( fields is the correct answer)

Irrigation was typically completed by digging canals leading from a water source (such as a river)  to the field. 

Ibelieve that would be a

Dall of the above all of the choices make sense