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198. A factory was trying out a new process for producing one of its products, with the goal of reducing production costs. A trial production run using the new process showed a 15 percent reduction in costs compared with past performance using the standard process. The production managers therefore concluded that the new process did produce a cost savings.

Which of the following, if true, casts most doubt on the production manager’s conclusion?

(D) Although some of the factory’s managers have been arguing that the product is outdated and ought to be redesigned, the use of the new production process does not involve any changes in the finished product.

(E) Since the new process differs from the standard process only in the way in which the stage of production are organized and ordered, the cost of the materials used in the product is the same in both processes.