Official Explanation

The conclusion of the argument is that the government should educate the public about medication usage if it wants to counteract the increase in complications from Disease $X$. The correct choice will show that education likely will not reduce complications from Disease $X$.
(A) The argument doesn't indicate which members of the public are most affected by Disease $X$, so it is unclear whether middle-school students are the relevant audience for this education program.
(B) The fact that the public already has access to this information through the internet does not say anything predictive about the effectiveness of the plan. People may not actually be reading the information.
(C) The way in which medications come to be prescribed by doctors has no bearing on whether the plan to educate the public about those medications will be effective in increasing their use.
(D) The argument recommends a specific plan; whether it eventually receives government funding is a separate issue.
(E) CORRECT. If the proper medications are unaffordable, educating people about those medications will do little to increase proper use and achieve the stated goal.