Which of the following, if true, most seriously weakens the argument given? A. The penalty for failed to pay the tax on a jar of cooking oil was not significantly greater than the price of the jar of oil. B. Even with the tax, the total cost of ajar of cooking oil for a Selean household declined steadily in the years just before and just after the tax was instituted. C. During the first two years after the tax was in effect, Selean law required merchants to sell cooking oil in jars of the same size as before the tax was instituted. D. The amount of oil used for cooking by Selean households increased after the implementation of the tax. E. The proportion of Selean households that produced their own cooking oil increased significantly after the implementation of the tax.