Food chain order: Arrange Grass, grasshopper, Frog, Snake, Eagle to represent a realistic terrestrial food chain from producer to top predator.

Introduction / Context:
Food chains begin with producers (plants) and progress through herbivores to carnivores. The question asks for an ecologically plausible chain for the listed organisms.

Given Data / Assumptions:

• Producer: Grass.
• Primary consumer: grasshopper (herbivore).
• Secondary consumer: Frog (insectivore).
• Tertiary consumer: Snake (predator of frogs).
• Apex predator: Eagle (can prey on snakes).

Concept / Approach:
Place organisms by trophic level from autotroph to apex predator.

Step-by-Step Solution:
Grass (producer) → grasshopper (primary consumer).→ Frog (secondary consumer).→ Snake (tertiary consumer).→ Eagle (apex consumer).

Verification / Alternative check:
Standard school ecology examples use exactly this chain.

Why Other Options Are Wrong:
They reverse consumer order or place predators before prey, violating trophic flow.

Common Pitfalls:
Forgetting that energy flows from producers upward; grass cannot consume animals.

Final Answer:
Grass, grasshopper, Frog, Snake, Eagle