Difficulty: Easy
Correct Answer: Sphere
Explanation:
Introduction / Context:Analogies may map a 2D figure to its standard 3D counterpart. A cube relates to a square (faces are squares); likewise, we select the 3D solid most directly corresponding to a circle.
Given Data / Assumptions:Circle is a 2D curve; the canonical 3D analogue formed by revolution about a diameter is a sphere.
Concept / Approach:Just as square → cube (3D extension), circle → sphere is the classic correspondence. Cone/cylinder use circular bases but are not the direct “circle → solid” counterpart in this canonical mapping.
Step-by-Step Solution:
1) Interpret mapping type: 2D shape → 3D solid. 2) Apply to circle: revolution about a diameter yields a sphere. 3) Pick “Sphere.”Why Other Options Are Wrong:Ellipse/parabola are 2D; cone/cylinder, while circular-based, are not the direct analogue in this standard pair.
Common Pitfalls:Choosing cone/cylinder because they involve circles, missing the canonical circle → sphere mapping.
Final Answer:Sphere
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