Select the set of classes whose relationship is best illustrated by the following diagram.
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → Birds, Parrots, Snakes
The diagram shows one circle inside a larger circle and a third circle apart from both. So one class must lie wholly within another, and the third class must share no member with either.
Option (1) Animals, Birds, Parrots — parrots are birds and birds are animals, so the three circles lie one inside another.
Option (2) Birds, Parrots, Snakes — every parrot is a bird, so the parrot circle lies inside the bird circle; a snake is not a bird, so its circle stays apart, as in the diagram.
Option (3) Insects, Birds, Snakes — no insect is a bird or a snake, and no bird is a snake, so all three circles stay apart.
Option (4) Birds, Sparrows, Parrots — sparrows and parrots are both birds, so two separate circles lie inside the bird circle.
