Find the odd animal (dietary habit): Select the carnivore among predominantly herbivorous animals.

Introduction / Context:
Classifying animals by primary diet provides a direct and unambiguous separator. Herbivores rely primarily on plant matter, while carnivores primarily consume other animals. A single carnivore among three herbivores yields a clear odd one out.

Given Data / Assumptions:

• Giraffe: herbivore feeding on foliage.
• Zebra: herbivore grazing on grasses.
• Horse: herbivore consuming grasses and forage.
• Lion: carnivore, apex predator hunting ungulates.

Concept / Approach:
Group by trophic level and diet. Three options are obligate or predominant herbivores; one is a carnivore. This ecological role distinction is standard in biology and supports an objective answer.

Step-by-Step Solution:

Verification / Alternative check:
Check dental and digestive adaptations: lions have carnassials and a carnivore gut; the others have herbivore dentition and digestive strategies.

Why Other Options Are Wrong:
They share plant-based diets and similar ecological niches as prey or grazers.

Common Pitfalls:
Size or habitat is not the deciding factor; diet is.

Final Answer:
Lion