Logical reasoning — Islands and volcanoes (choose the statement that must be true) Facts: Islands are surrounded by water. Maui is an island. Maui was formed by a volcano. Which statement must also be a fact?

Introduction / Context:
This is a straightforward application of categorical logic. From a universal statement about islands and a specific statement identifying Maui as an island, we can infer a specific property about Maui. We must resist adding universal claims about volcanoes that are not provided.

Given Data / Assumptions:

• All islands are surrounded by water.
• Maui belongs to the set of islands.
• Maui's geological origin involves a volcano, but nothing is said about other islands or all volcanoes.

Concept / Approach:
Apply universal instantiation: if all elements of a set have property P, and X is a member of that set, then X has property P. Do not generalize from a single example (Maui) to all islands or all volcanoes.

Step-by-Step Solution:

Verification / Alternative check:
Generic logic pattern: All A are B; X is A; therefore X is B. This matches 1) and 2). Statements II and III attempt unjustified universal generalizations.

Why Other Options Are Wrong:

• II only / II and III only: Overgeneralize beyond the data.
• None of the statements is a known fact.: Incorrect because statement I is certain.
• I and II only: Includes an unjustified generalization (II).

Common Pitfalls:
Confusing an example (“Maui was formed by a volcano”) with a universal law applying to all islands or all volcanoes.

Final Answer:
I only