The autotrophic mode of nutrition requires :

Options

A. carbon dioxide and water.
B. sunlight.
C. chlorophyll.
D. all of the above

Answer

### Step-by-Step Solution:

1. **Understanding Autotrophic Nutrition**:
- Autotrophic nutrition is a mode of nutrition where organisms can produce their own food. This is primarily seen in green plants.

2. **Key Components Required**:
- To perform autotrophic nutrition, specifically through the process of photosynthesis, certain raw materials are essential.

3. **Identifying the Raw Materials**:
- The primary raw materials needed for autotrophic nutrition are:
- **Carbon Dioxide (CO2)**: This gas is absorbed from the atmosphere through the stomata in the leaves.
- **Water (H2O)**: Water is absorbed by the roots from the soil.
- **Sunlight**: Sunlight is captured by the chlorophyll present in the chloroplasts of plant cells.
- **Chlorophyll**: This green pigment is crucial as it helps in capturing sunlight for the process of photosynthesis.

4. **The Process of Photosynthesis**:
- Using the above raw materials (CO2, H2O, sunlight, and chlorophyll), green plants convert these into glucose (food) and oxygen through the process known as photosynthesis.

5. **Conclusion**:
- Therefore, the autotrophic mode of nutrition requires carbon dioxide, water, sunlight, and chlorophyll.