Verification of truth — necessary attribute: A cupboard always has what essential part?

Introduction / Context:
We must decide which component is intrinsic to the very idea of a “cupboard.” Everyday usage distinguishes a cupboard (an enclosed storage cabinet) from open shelving or racks.

Given Data / Assumptions:

• “Cupboard” denotes an enclosed storage piece or recess fitted with doors.
• Internal configuration (shelves, bolts) varies; contents (clothes) are not definitional.

Concept / Approach:
Identify what differentiates a cupboard from other storage: enclosure via a door. Shelves may be present but are not mandatory; many cupboards have hanging space or bins. A bolt/lock is optional security hardware.

Step-by-Step Solution:

Verification / Alternative check:
Remove the door and the unit becomes an open shelf; with a door, it meets the cupboard definition even without shelves.

Why Other Options Are Wrong:

• Clothes: Cupboards can store many items, not only clothes.
• Shelf: Some cupboards are for hanging/storage without shelves.
• Bolt: Optional.
• None of these: Incorrect since “Door” is required.

Common Pitfalls:

• Assuming shelves are mandatory; design varies widely.

Final Answer:

Door