Analogy — Antonym by quality: Deep : Shallow :: Sharp : ? Pick the antonym that stands to “Sharp” as “Shallow” stands to “Deep”.

Introduction / Context:
The first pair is an antonymic quality contrast. We must supply the opposite quality for “Sharp”.

Given Data / Assumptions:

• Deep ↔ Shallow (antonyms describing extent).
• Sharp ↔ ? (antonym describing edge/acuity).
• Options include nouns (Knife, Blade, Ocean) and an adjective (Blunt).

Concept / Approach:
Maintain part-of-speech and semantic field. “Sharp” is an adjective describing an edge; its standard antonym is “Blunt”.

Step-by-Step Solution:

Verification / Alternative check:
Dictionary antonyms: sharp ↔ blunt.

Why Other Options Are Wrong:

• Knife/Blade/Ocean: Not antonyms; mismatched parts of speech.
• None of these: Invalid since “Blunt” fits.

Common Pitfalls:
Picking a related noun (Knife/Blade) due to association with sharpness, rather than selecting the opposite quality.

Final Answer:
Blunt