Which of the following is not a producer?

Options

A. Spirogyra
B. Agaricus
C. Volvox
D. Nostoc

Answer

To determine which of the following is not a producer, we need to analyze each option provided. Producers are organisms that can make their own food through photosynthesis or chemosynthesis, typically using sunlight or chemical energy.

### Step-by-Step Solution:

1. **Identify the Options**: We need to look at the four options given in the question. Let's assume they are:
- A) Spirogyra
- B) Agricus
- C) Volvox
- D) Nostoc

2. **Analyze Spirogyra**:
- Spirogyra is a type of green algae.
- It contains chlorophyll and is capable of photosynthesis.
- Therefore, Spirogyra is a producer.

3. **Analyze Agricus**:
- Agricus, commonly known as the mushroom, is a fungus.
- Fungi do not contain chlorophyll and cannot perform photosynthesis.
- Instead, they obtain nutrients by decomposing organic matter.
- Therefore, Agricus is **not** a producer.

4. **Analyze Volvox**:
- Volvox is a green algae that forms spherical colonies.
- It also contains chlorophyll and can perform photosynthesis.
- Therefore, Volvox is a producer.

5. **Analyze Nostoc**:
- Nostoc is a cyanobacterium that can photosynthesize.
- It contains chlorophyll and can produce its own food.
- Therefore, Nostoc is a producer.

6. **Conclusion**:
- Among the options analyzed, Agricus is the only organism that does not produce its own food and is therefore not a producer.
- The correct answer is **B) Agricus**.

### Final Answer:
**B) Agricus** is not a producer.