According to the newly published guidelines from the city zoning board, a neighborhood can be officially designated as a 'quiet zone' only if it has absolutely no commercial businesses operating within its boundaries. The residents of the Maplewood neighborhood recently submitted an extensive application requesting this special designation. However, it is clear that the Maplewood neighborhood will not be designated as a 'quiet zone' this year.
Which one of the following, if assumed, enables the conclusion to be properly drawn?
- AIf the Maplewood neighborhood had no commercial businesses operating within its boundaries, it would be designated as a 'quiet zone'.
- BThe Maplewood neighborhood is located immediately adjacent to the city's largest and most active commercial district.
- There is at least one commercial business currently operating within the boundaries of the Maplewood neighborhood.Answer
- DThe Maplewood neighborhood features several large buildings that were originally constructed for commercial use.
- EThe city zoning board is actively trying to decrease the total number of designated 'quiet zones' across the city.
Answer
The assumption that there is at least one commercial business operating within the boundaries of the Maplewood neighborhood.
The argument provides a strict conditional rule: if a neighborhood is a 'quiet zone', then it has absolutely no commercial businesses operating within it. The conclusion states that Maplewood will not be a 'quiet zone'. To properly draw this conclusion, we must trigger the contrapositive of the rule: if a neighborhood DOES have a commercial business operating within it, it cannot be a 'quiet zone'. The correct answer perfectly supplies this missing fact by stating that Maplewood currently has at least one commercial business operating within its boundaries, which logically guarantees the conclusion.
Step-by-Step Solution
Key Concept
Identifying Sufficient Assumptions via Contrapositive Logic