'Mountain' contrasts with 'Valley' (opposites in relief/landform); sustaining the same opposition pattern, 'Enemy' contrasts with which term?

Introduction / Context:
Contrast-based analogies pair items that stand in clear opposition within a category. A 'mountain' is an elevated landform, while a 'valley' is a low-lying landform between hills or mountains; they are conceptual opposites in physiographic relief. We must find the direct opposite of 'enemy' in a relationship sense.

Given Data / Assumptions:

• Mountain vs valley expresses reversed features within the same domain (topographic elevation).
• Enemy is a relational term describing hostility or opposition.
• We seek the precise antonym that mirrors the relation as tightly as 'valley' mirrors 'mountain'.

Concept / Approach:
Preserve both domain and polarity: choose a term that is the standard antonym in social/relational context. 'Friend' is the canonical opposite of 'enemy'—the shift from hostility to amity mirrors the shift from high relief to low relief in the first pair.

Step-by-Step Solution:
1) Identify relation type: strict opposites within the same domain.2) Apply to second pair: enemy → ?3) The standard antonym is friend.4) Select 'Friend' to maintain the analogy's symmetry.

Verification / Alternative check:
General English usage, dictionaries, and logic problems routinely present 'enemy ↔ friend' as antonyms, validating the mapping.

Why Other Options Are Wrong:

• Cruel: An adjective describing behavior; not the antonym of the noun 'enemy'.
• Stranger: Neutral relational status; not opposite to 'enemy'.
• Country: Category mismatch; a geopolitical unit, not a relational antonym.
• None of these: Incorrect because 'Friend' is correct.

Common Pitfalls:
Selecting a vaguely positive word rather than the true antonym. The best analogies retain exact relational polarity.

Final Answer:
Friend