Why does a food chain usually start from a producer?

Explanation

### Step-by-Step Solution:

1. **Understanding Producers**: The food chain begins with producers, which are primarily green plants. These plants are called producers because they can create their own food.

2. **Photosynthesis Process**: Producers utilize sunlight, chlorophyll, water, and carbon dioxide (CO2) to produce food through a process known as photosynthesis. This process allows them to convert these raw materials into energy-rich food.

3. **Independence of Producers**: Unlike other organisms, producers do not rely on other living beings for their food. They are independent because they can synthesize their own food.

...