Teenagers are often priced out of the labor market by the government-mandated minimum-wage level because employers cannot afford to pay that much for extra help. Therefore, if Congress institutes a subminimum wage, a new lower legal wage for teenagers, the teenage unemployment rate, which has been rising since 1960, will no longer increase. Which of the following, if true, would most weaken the argument above? (A) Since 1960 the teenage unemployment rate has risen when the minimum wage has risen. (B) Since 1960 the teenage unemployment rate has risen even when the minimum wage remained constant. (C) Employers often hire extra help during holiday and warm weather seasons. (D) The teenage unemployment rate rose more quickly in the 1970’s than it did in the 1960’s. (E) The teenage unemployment rate has occasionally declined in the years since 1960.

我不知道为什么B对。最低工资水平保持不变说明什么啊？好比1960年的最低工资水平是100元，10年没变，雇主一直觉得100元太贵，所以青少年失业率一直上升。现在提出新标准，最低水平变为80元，雇主觉得可以接受，于是青少年失业率就不会再上升了。B怎么就可以削弱啊？