Classification — find the group with all members from a single category: Which option lists three items of the same kind?

Introduction / Context:
This is a “pick the uniform set” classification problem. Exactly one option groups three members of a single, unambiguous category. The other options intentionally mix categories to distract you (animals with plants, places with objects, etc.). The most reliable approach is to label each item with a concise category (bird, mammal, plant, country, object) and see which option yields three identical labels.

Given Data / Assumptions:

• Ostrich, Hen, Swan — all birds (avian species).
• Duck, Lion, Horse — animal + animal + animal, but two are mammals (lion, horse) while duck is a bird (mixed classes).
• Zebra, Cabbage, Rose — mammal + plant (vegetable) + plant (flower) (mixed kingdom roles).
• India, World, Mobile — country + planet/earth/“world” concept + handheld device (mixed and cross-domain).

Concept / Approach:
Labeling by high-level taxonomy cuts through ambiguity. Option A maps to “bird, bird, bird.” Options B–D each contain heterogeneous labels and therefore cannot represent a single coherent class. In verbal reasoning, uniform taxonomy (same super-category) is the canonical discriminator.

Step-by-Step Solution:
1) Tag A: bird/bird/bird → uniform.2) Tag B: bird/mammal/mammal → mixed.3) Tag C: mammal/plant/plant → mixed.4) Tag D: country/planet-or-collective/device → mixed.

Verification / Alternative check:
Substitute each group into “All three are types of ______.” Only A reasonably completes as “All three are types of birds.” Any attempt to complete this sentence for B–D quickly exposes the heterogeneity (e.g., “All three are animals” fails in C and D; “All three are places” fails in D, etc.).

Why Other Options Are Wrong:

• B: mixes avian and mammalian animals.
• C: mixes an animal with two plants.
• D: mixes geopolitics/astronomy with consumer electronics.

Common Pitfalls:
Assuming “all are living/non-living” is sufficient. The test expects a single, specific super-category, not a vague commonality.

Final Answer:
Ostrich, Hen, Swan