Analogy completion — choose the best word to complete the relationship: table : wood : oak :: shirt : cloth : __

Introduction / Context:
This analogy checks recognition of material, category, and subtype. A table is made from the material 'wood,' and 'oak' is a specific type of wood. Likewise, a shirt is made from the material 'cloth,' and you must supply a specific subtype of cloth to keep the pattern parallel.

Given Data / Assumptions:

• Object → material → subtype: table → wood → oak.
• Object → material → subtype: shirt → cloth → __.
• We need a common fabric subtype that fits the second chain.

Concept / Approach:
Keep the hierarchy identical. 'Oak' is a subtype of 'wood.' Therefore the blank should be a subtype of 'cloth' used to make shirts. 'Cotton' is a widely used fabric for shirts and is a standard subtype under cloth/textile materials. Other alternatives either change the level (process or object) or do not represent a fabric subtype.

Step-by-Step Solution:

Verification / Alternative check:
Ask whether the proposed word is a material used to make the item. Cotton is a cloth; 'tree' is the source of wood, not fabric; 'sewing' is a process; 'dress' is another garment; 'polymer' is a material class but not typically the fabric name for shirts in everyday usage (better examples would be polyester or nylon). Hence, 'cotton' is the most natural and parallel choice.

Why Other Options Are Wrong:

• tree: source category for wood; wrong level and domain.
• sewing: a process, not a material subtype.
• dress: an object, not a material.
• polymer: too abstract and not the common fabric name used for shirts.

Common Pitfalls:
Confusing source, process, or product levels. Keep the analogy's hierarchy consistent: object → material → subtype of that material.

Final Answer:
cotton