Iron, silver, and gold are examples drawn from the same material category. Which option mirrors “example : example : example (same class)”?

Introduction / Context:
Pure-class analogies present three members of the same category. Iron, silver, and gold are all metals (elements in the periodic table). The correct choice should similarly list three items that belong to one natural class without mixing a class label among the examples.

Given Data / Assumptions:
We must avoid options that blend “examples + class name”, which breaks the parallel structure.

Concept / Approach:
“Deer : Lion : Wolf” offers three animal species, all members of the class “animals” (specifically mammals). This mirrors the “example : example : example” structure of the stem. Options that inject the category name (e.g., “cereal”) alongside examples or that mix parts/typos (“brench”) violate the pattern.

Step-by-Step Solution:

Verification / Alternative check:
“Wheat : Barley : Cereal” mixes two examples with the class name; “Parents : Father : Mother” mixes a relation term with role terms; “Tree : Brench : Fruit” includes a misspelling and mixed hierarchy.

Why Other Options Are Wrong:
They either blend class and members or contain category/part inconsistencies.

Common Pitfalls:
Noticing familiar words but missing that the structural pattern must remain “all members, no class label”.

Final Answer:
Deer : Lion : Wolf