Which of the following diagrams indicates the best relation between Sailor,…

Concept: In Venn-diagram reasoning, the diagram used for three items depends on how their categories relate: separate circles show unrelated (disjoint) items, partly overlapping circles show items that share only some members, and circles drawn one strictly inside another show a chain of full containment, where every member of the inner circle is also a member of the outer one.

Application: Here every sailor works on a ship, so the set of sailors sits entirely inside the set that belongs to ships; and every ship operates in the ocean, so the set of ships sits entirely inside the ocean. That gives a two-level full-containment chain: Sailor inside Ship inside Ocean, with nothing left outside the next larger circle.

• Three circles that all overlap one another describe partial sharing between every pair, not full containment, so that diagram does not fit.

• Two separate circles placed inside one larger circle describe two independent categories under a common outer category, which misses that one of the two is supposed to sit entirely inside the other.

• One pair of nested circles next to a third, fully separate circle captures only part of the chain nested, leaving the remaining entity unconnected, so it does not show all three levels in a single chain.

The diagram of three circles drawn one strictly inside the other, smallest to largest, correctly represents Sailor inside Ship inside Ocean.