Geometry

Question Analysis
This question tests visual recognition of cone types.
The main focus is distinguishing oblique cones (tilted apex) from other variants.

Key Concept Explanation
Oblique Cone: The apex is not perpendicular to the base’s center; it appears "leaning."
Right Cone (A): Apex is perfectly centered.
Frustum (C): A cone with the top sliced off parallel to the base.
Elliptical Cone (D): Defined by its oval base, not apex alignment.

Step-by-Step Solution
Eliminate A (right cone) and C (frustum) based on definitions.
D has an elliptical base ...