假设求助

The program to control the entry of illegal drugs into the country was a failure in 1987. If the program had been successful, the wholesale price of most illegal drugs would not have dropped substantially in 1987.

The argument in the passage depends on which of the following assumptions?

1. The supplysupply of illegal drugs substantially in 1987.

2. The price paid for most illegal drugs by the average consumer did not drop substantially in 1987.

3. Domestic production of illegal drugs increased at a higher rate than did the entry of such drugs into the country.

4. The wholesale price of a few illegal drugs increased substantially in 1987.

5. A drop in demand for most illegal drugs in 1987 was not the sole cause of the drop in their wholesale price.

请大家帮帮我，为什么假设是5

题目的意思是说如果那个program成功了的话 违禁药的价格就不会下降了

所以违禁药的价格下降不是因为这个program 所以要找一个别的原因来解释价格的下降

那就是 drop in demand 了

其实我都分不清问问题的时候这种assumption或者那种assumption有啥区别 唉

谢谢，觉得有时候这种转点弯子的题目搞不太清楚，痛苦。。。。。。