A: We have no information about price of the new pencils.
B: I was trapped into choosing this choice. While its more supportive than A,C, and D, it's wrong bc we're not told anything specific about the WC-- just a general market trend.
C: Them studying doesn't necessarily mean the plan is more likely to work.
D: This weakens the plan.
E: I initially discounted this, thinking that just because users found it superior, doesn't necessarily mean that its sales will increase. But unlike B, E does specifically mention WC, and gives us a reason to believe that the superior quality will increase sales.
Takeaway: Because this choice mentions a specific plan in regards to a specific company, choices about general upward trends won't work here. Choose the choice that specifically poses a benefit the company (E).