Find the odd word (church items vs unrelated term): Pick the option that does not commonly denote a church furnishing or group.

Introduction / Context:
Semantic fields provide clean grouping. Three words denote items or groups associated with a church setting, while one denotes a personal quality unrelated to church furnishings or roles. Correcting a likely misspelling, Altar (not Alter) is the intended sacred table in a church.

Given Data / Assumptions:

• Pew: bench seating in a church.
• Altar: sacred table or structure in a church.
• Choir: organized group of singers in a church service context.
• Mettle: a person's resilience or spirit; not a church furnishing or group.

Concept / Approach:
Group tokens by domain relevance to church architecture and liturgy. Three belong to the ecclesiastical domain; one is general abstract vocabulary.

Step-by-Step Solution:

Verification / Alternative check:
Attempt to use each in a sentence about church interiors; mettle does not fit as an object or role within the building.

Why Other Options Are Wrong:
They are standard components or groups in church services or interiors.

Common Pitfalls:
Do not confuse Alter with Altar; the corrected church term is Altar.

Final Answer:
Mettle