Difficulty: Medium
Correct Answer: None of the four
Explanation:
Introduction / Context:
This item explores how multiple subset and “some” statements interact. The trap is to assume overlaps that are not guaranteed by the premises, especially when two separate “some” statements could refer to different subgroups.
Given Data / Assumptions:
Concept / Approach:
We must test whether a conclusion must be true in every model satisfying the premises. If a counterexample exists, that conclusion does not follow. Separate “some” statements may refer to disjoint elements unless a link forces the same individuals to be shared.
Step-by-Step Solution:
Verification / Alternative check:
Because nothing requires the “some papers that are journals” to be the same individuals as the “some journals that are calendars,” overlaps with books or calendars are not forced. Hence none of the conclusions must follow.
Why Other Options Are Wrong:
Common Pitfalls:
Chaining separate “some” facts as if they refer to the same elements. Without an “all” or explicit identity, such chaining is invalid.
Final Answer:
None of the four
Discussion & Comments