Choose the incorrect food chain.

Options

A. Grass `to` Grasshopper `to` Frog ` to` Snake `to` Eagle
B. Phytoplanktons `to` Zooplanktons `to` Small fish `to` Large fish
C. Diatoms `to` Zooplanktons `to` Small fish
D. Grass `to` Frog `to` Vulture

Answer

To choose the incorrect food chain from the given options, we will analyze each food chain step by step.

### Step-by-Step Solution:

1. **Understanding Food Chains**: A food chain represents the flow of energy from one organism to another in an ecosystem. It typically starts with producers (organisms that can synthesize their own food) and moves up to primary consumers (herbivores), secondary consumers (carnivores that eat herbivores), and so on.

2. **Analyzing Each Option**:
- **Option A**: Grass → Grasshopper → Frog → Snake → Eagle
- Grass is a producer.
- Grasshopper is a primary consumer (herbivore).
- Frog is a secondary consumer (carnivore).
- Snake is a tertiary consumer.
- Eagle is a quaternary consumer.
- **Conclusion**: This food chain is correct.

- **Option B**: Phytoplankton → Zooplankton → Small Fish → Large Fish
- Phytoplankton is a producer.
- Zooplankton is a primary consumer (herbivore).
- Small fish are secondary consumers.
- Large fish are tertiary consumers.
- **Conclusion**: This food chain is correct.

- **Option C**: Diatom → Zooplankton → Small Fish
- Diatoms are producers.
- Zooplankton are primary consumers.
- Small fish are secondary consumers.
- **Conclusion**: This food chain is correct.

- **Option D**: Grass → Frog → Vulture
- Grass is a producer.
- Frog is typically a secondary consumer, but it cannot feed directly on grass; it needs to feed on a primary consumer (like a grasshopper).
- Vulture is a tertiary consumer that feeds on dead animals.
- **Conclusion**: This food chain is incorrect because it lacks a primary consumer.

3. **Final Answer**: The incorrect food chain is **Option D: Grass → Frog → Vulture**.