Teenagers are often priced out of the labor market by the government-m

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.

Answer is not E but B. Let's discuss why not E. Let me know what is your logic.

What i understand from the passage is that 'owners are not willing to pay government-mandated minimum-wage level to teenagers for extra help .[ Attention this is not regular work , author refers to extra work ]. The author concludes that if Congress institutes a subminimum wage, then unemployment rate which has been rising since 1960 will no longer increase.

Here assumption is that by institutionalizing a sub minimum wage for teenagers , unemployment rate will not increase.

We need to weaken this assumption .

Let us pre think on how to do weaken by considering some scenarios
a) Even after Institutionalizing a sub minimum wage for teenagers, if Unemployment rate does not decrease --- weakens
b) There may be another reason for the cause of Unemployment. --- weakens

Let us walk through the options B and C which provide us with similar kind of scenarios

Choice C : Employers often hire extra help during holiday and warm weather seasons. [This choice talks about extra help]

So this weakens the argument that even after Institutionalizing a sub minimum wage for teenagers, as employers hire for extra help only during holiday season, this doesn't reduce unemployment.

Choice B : Since 1960 the teenage unemployment rate has risen even when the minimum wage remained constant.
This argument is already given in the question that " teenage unemployment rate which has been rising since 1960" and the cause of this effect was wage was higher (remained constant)
I would have rather choosen B , if the statement given was as following

"Since 1960 the teenage unemployment rate has risen even after Institutionalizing a sub minimum wage for teenagers" .
(or)
In case of choice B should we assume that government will be increasing the minimum wage every year, and inspite of not increasing the minimum wage , still there is unemployment. Hence reckoned as a Weakaner.

Kindly help me on this question.
Thanks in advance