Analogy — “Oval : Circle :: Rectangle : ?”. Choose the figure that is a special case of the first, preserving the “general shape → special case” relation.

Introduction / Context:
The pair “Oval : Circle” can be read as “general shape → special case.” A circle is a special kind of oval (in informal usage; more precisely, a circle is a special ellipse with equal axes). We must find a parallel relation for “Rectangle : ?”.

Given Data / Assumptions:

• Maintain the direction: broader class → special instance.
• All terms should belong to the 2D shape family.

Concept / Approach:
Among plane figures, a square is a special rectangle (all sides equal, angles 90°), fitting the same class–subclass relation as circle to oval/ellipse.

Step-by-Step Solution:

Verification / Alternative check:
Geometric hierarchy confirms square ⊂ rectangle.

Why Other Options Are Wrong:
They are not special cases of rectangles or are unrelated properties.

Common Pitfalls:
Confusing shape properties (diagonal, periphery) with shapes.

Final Answer:
Square