Researchers have studied the cost-effectiveness of growing halophytes—salt-tolerant plant species—for animal forage. Halophytes require more water than conventional crops, but can be irrigated with seawater, and pumping seawater into farms near sea level is much cheaper than pumping freshwater from deep wells. Thus, seawater agriculture near sea level should be cost-effective in desert regions although its yields are smaller than traditional, freshwater agriculture.

Which one of the following, if true, most strengthens the argument above?
(A) A given volume of halophytes is significantly different in nutritional value for animal forage from the same volume of conventional forage crops.
(B) Some halophytes not only tolerate seawater but require salt in order to thrive.
(C) Large research expenditures are needed to develop the strains of halophytes best suited for agricultural purposes.
(D) Costs other than the costs of irrigation are different for halophytes grown by means of seawater irrigation than for conventional crops.
(E) Pumping water for irrigation is proportionally one of the largest costs involved in growing, harvesting, and distributing any forage crop for animals.
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Conclusion: Agriculture in desert which is near sea level is cost-effective if we use seawater than freshwater.
Why? Because pumping seawater into farms near sea level is much cheaper than pumping freshwater from deep wells
Therefore, We are looking for a strengthener with cost aspect to it.

Which one of the following, if true, most strengthens the argument above?


We are not concerned about the nutritional value of halophytes.


Not covering the cost aspect.


This option is touching the cost aspect but research expenditures is out of scope. We are interested in the cost effectiveness of using sea water for agriculture.


This option is saying that there is difference in cost when you irrigate halophytes with sea water and when you irrigate conventional crops with sea water. It does not tell us whether this difference is good(cost effective difference) or bad(expensive) difference. Also cost of irrigation of conventional crops with sea water is out of scope.


There might be several costs involved in growing, harvesting, and distributing any forage crop(halophyte/conventional) for animal forage. But Pumping water for irrigation is one of the largest costs and pumping sea water cuts down this major cost.
Hence, sea water is cost effective.
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