I’m happy to help. As always, let’s start with the question stem. We are looking for the answer that describes an error of reasoning in the merchants’ argument. So what was that argument?
The merchants are protesting the outdoor advertising ban proposal, because they think the law would reduce the overall volume of business. What is the evidence for that claim? They point to a report indicating that in every industry the businesses that used outdoor advertising had a larger market share.
Before you look at answer options, try to describe the flaw in your own mind. I would describe it as: there seems to be a gap in the argument, insofar as the evidence the merchants point to is about relative market share of businesses that use outdoor advertising and those that don’t, and a conclusion that is about a reduction in “overall volume of business.†That is a logical gap! Why couldn’t it be true that the outdoor advertising businesses would lose their relative market share advantage if the new law came into effect, but that the business would just go to other businesses in Penglai, thus creating no reduction in the overall volume of business in Penglai?
And that is exactly what answer B states. The argument assumes that outdoor advertising “increased market share by some means other than by diverting trade from competing businesses.†Because if the outdoor advertising simply diverted trade from competing businesses, the ban on outdoor advertising would have no impact on the overall volume of business in Penglai.
Answer D on the other hand states that the argument failed to establish whether the market share advantage of businesses using outdoor advertising “was precisely proportionate to the amount of advertising.†It doesn’t matter for the purpose of the merchants’ argument whether the market share to advertising ratio was “precisely proportionate†— instead, the flaw is about the lack of connection between the evidence of market share and advertising to the reduction of “overall business volume.â€
I hope that helps! Please let us know if you have further questions.
