Brain scans of people exposed to certain neurotoxins reveal brain damage identical to that found in people suffering ...

Reading this stimulus, I didn't feel as though the author was overestimating the importance of early prevention. In all honesty, I didn't think the author was even trying to highlight the importance of early detection/prevention, let alone over estimating its importance. What am i missing in this argument that, if I had picked up on, would have led me to choose the correct answer?