It is possible to grow agricultural crops that can thrive when irrigated with seawater. Such farming, if undertaken near oceans, would actually be cheaper than most other irrigated agriculture, since the water would not have to be pumped far. The greatest expense in irrigated agriculture is in pumping the water, and the pumping costs increase with the distance the water is pumped. Which one of the following most accurately describes the role played in the argument by the claim that the greatest expense in irrigated agriculture is in pumping the water? ["It is a claim for which the argument provides evidence, but which is not the argument's conclusion.", 'It is a claim that the argument shows to be false.', "It is evidence provided to support the argument's conclusion.", "It is the argument's conclusion."]