Which of the following statements about the autotrophs is incorrect?

Options

A. They synthesise carbohydrates from carbon dioxide and water in the presence of sunlight and chlorophyll
B. They store carbohydrates in the form of starch
C. They carbon dioxide and water into carbohydrates in the absence of sunlight
D. They constitute the first trophic level in food chains

Explanation

To determine which statement about autotrophs is incorrect, we can analyze each statement based on our understanding of autotrophs and their functions.

1. **Understanding Autotrophs**: Autotrophs are organisms that produce their own food. They utilize carbon dioxide, water, and sunlight, along with chlorophyll, to synthesize carbohydrates through a process known as photosynthesis.

2. **Evaluating the Statements**:
- **Statement 1**: "The synthesized carbohydrates or food from carbon dioxide and water in the presence of sunlight and chlorophyll."
- This statement is correct because autotrophs do synthesize carbohydrates using these materials during photosynthesis.

- **Statement 2**: "They store carbohydrates in the form of starch."
- This statement is also correct. Plants, which are autotrophs, store carbohydrates primarily as starch.

- **Statement 3**: "They convert carbon dioxide and water into carbohydrates in the absence of sunlight."
- This statement is incorrect. Photosynthesis requires sunlight; without it, autotrophs cannot produce carbohydrates.

- **Statement 4**: "They constitute the first trophic level in the food chain."
- This statement is correct. Autotrophs are indeed the primary producers and form the first trophic level in food chains.

3. **Conclusion**: The only incorrect statement about autotrophs is Statement 3, which claims that they can convert carbon dioxide and water into carbohydrates without sunlight.

### Final Answer:
The incorrect statement about autotrophs is: **"They convert carbon dioxide and water into carbohydrates in the absence of sunlight."**