The average hourly wage of television assemblers in Vernland has long been significantly lower than that in neighboring Borodia. Since Borodia dropped all tariffs on Vernlandian televisions three years ago, the number of televisions sold annually in Borodia has not changed. However, recent statistics show a drop in the number of television assemblers in Borodia. Therefore, updated trade statistics will probably indicate that the number of televisions Borodia imports annually from Vernland has increased.
Which of the following is an assumption on which the argument depends?
A. The number of television assemblers in Vernland has increased by at least as much as the number of television assemblers in Borodia has decreased.
B. Televisions assembled in Vernland have features that televisions assembled in Borodia do not have.
C. The average number of hours it takes a Borodian television assembler to assemble a television has not decreased significantly during the past three years.
D. The number of televisions assembled annually in Vernland has increased significantly during the past three years.
E. The difference between the hourly wage of television assemblers in Vernland and the hourly wage of television assemblers in Borodia is likely to decrease in the next few years.
求助各位XDJM，不明白，我选了A啊...为什么答案是C？？？谢谢解答~ | 
