Choose the Venn diagram from the given options which represents the correct…

In a classification Venn diagram, the circles for two classes must match how those classes actually relate: one circle sits fully inside the other only when EVERY member of the smaller class is also a member of the larger class (full inclusion); the circles intersect only when the classes share SOME but not all members (a partial overlap); and the circles stay completely separate when the classes share NO members at all (a disjoint relationship).

1. A shark is a type of cartilaginous fish, so every shark is classified as a fish: the class “Shark” is entirely contained within the class “Fish” — a full-inclusion relationship, not a partial overlap.

2. A starfish, despite its name, is not a fish at all — it belongs to a completely different animal group (Echinodermata) and shares no members with either “Fish” or “Shark” — a fully disjoint relationship.

3. Combining both facts: the correct diagram needs one small circle placed wholly inside a larger circle (Shark inside Fish), plus one separate circle that does not touch either of the other two (Starfish, standing apart).

• A diagram built as a chain of partial overlaps (each circle touching only its immediate neighbour, so the two end circles never meet) wrongly treats every pairing here as a partial overlap — but the Shark–Fish relationship is full inclusion, not a partial share, and Starfish shares nothing with either, so no pair here is a genuine partial overlap.

• A diagram with two equal, separate circles both sitting inside one larger circle wrongly treats the two smaller classes as equally-ranked subsets of the larger class — but only one of the two smaller classes here actually belongs inside the larger one; the other does not belong inside it at all.

• A diagram with two overlapping circles plus a smaller circle nested specifically inside their shared overlap region wrongly assumes two of the three classes partially overlap each other, with the third confined to just that shared zone — but none of the three pairs here is a partial overlap in the first place.

• The diagram with a small circle fully inside a larger circle, plus a separate third circle touching neither, is the only pattern that captures both facts at once: full inclusion for the Shark–Fish pair, and complete separation for Starfish from both.