In solid geometry, is it correct that a solid body is bounded by the surfaces that enclose its volume (e.g., planes, cylinders, spheres forming the outer boundary)?

Introduction / Context:
Basic definitions anchor all higher-level modeling and drafting work. A solid occupies volume; its boundary is a closed set of surfaces. Recognizing this helps in feature operations (shell, fillet), sectioning, and mass property evaluation in CAD.

Given Data / Assumptions:

• Solids are 3D regions with interior volume.
• Bounding surfaces may be planar or curved.
• The boundary is closed (no gaps) to enclose volume.

Concept / Approach:
The definition of a solid includes an external boundary forming a manifold surface. Whether piecewise planar (polyhedra) or smoothly curved (spheres), the enclosing surfaces separate interior from exterior, enabling volume, centroid, and inertia calculations.

Step-by-Step Solution:

Verification / Alternative check:
In CAD, viewing section cuts shows a finite interior. Mass properties require a watertight boundary, reinforcing the definition.

Why Other Options Are Wrong:
Limiting truth to prisms or planar faces ignores curved solids; projection/view choice does not affect geometric definition.

Common Pitfalls:
Confusing wireframe (no surface) with solids; mistaking open surfaces (no volume) for solids.

Final Answer:
Correct