"If the public library shared by the adjacent towns of Redville and Glenwood were relocated from the library's current, overcrowded building in central Redville to a larger, available building in central Glenwood, the library would then be within walking distance of a larger number of library users."
The evidence provided to support this argument is that "there are many more people living in central Glenwood than in central Redville, and people generally will walk to the library only if it is located close to their homes."
Overall, the passage is arguing that, if the library were moved from Redville to Glenwood, the library would be within walking distance of a greater number of library users because there are more people in Glenwood than Redville and people generally walk to the library only if it is close to home.
Answer choice A is incorrect because it does not impact the argument. The passage argues that moving the library to Glenwood would mean the library would be within walking distance of a greater number of library users. We also know from the passage that people generally walk to the library only if it is located close to home. As the library is currently located in Redville, it makes sense that more people who currently walk to the library live in Redville. While moving the library would make it farther from these current users, the passage is arguing that the library would then be within walking distance of a larger number of library users as the population of central Glenwood is larger.
B is the correct answer choice because it weakens the argument. The passage argues that moving the library would mean that it would be within walking distance of a larger number of library users. However, this answer choice tells us that fewer people in central Glenwood would use the library than currently do in central Redville. This negates the argument's conclusion that the library would be within walking distance of a greater number of users because the people would not be using the library and, therefore, would not be considered users. This means that the library would be within walking distance of a similar or smaller number of users in Glenwood than in Redville.
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