In the following question, arguments are followed by four diagrams. Choose the correct diagram that shows/represents the argument correctly.
All boys are houses
No houses are huts
No huts are boys
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) →
In a Venn diagram, “All X are Y” puts circle X wholly inside circle Y, and “No X are Y” keeps the two circles apart.
All boys are houses: the Boys circle lies inside the Houses circle
No houses are huts: the Huts circle stays outside the Houses circle
No huts are boys: the boys are inside the houses, so the huts cannot touch them either
Option (1) shows Boys inside Houses, with Huts apart from both.
Why the other options are incorrect
Option (2) — Incorrect. Huts overlaps Houses, so some houses would be huts.
Option (3) — Incorrect. Huts overlaps both Houses and Boys.
Option (4) — Incorrect. It puts Houses inside Boys (all houses are boys), the wrong way round.