Commercial source of manufacture of citric acid is

Options

A. Citrus fruits
B. Aspergillus
C. Bacteria
D. Penicillium

Answer

To solve the question regarding the commercial source of manufacture of citric acid, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for the commercial source of citric acid, which implies we are looking for a source that can produce citric acid on a large scale.

2. **Evaluate the Options**:
- **Option 1: Citrus Fruits**: While citrus fruits like lemons and oranges contain citric acid, they do so in small amounts and are not used for large-scale production.
- **Option 2: Aspergillus**: This is a genus of fungi, specifically Aspergillus niger, which is known for its ability to produce citric acid in large quantities through fermentation processes.
- **Option 3: Bacteria**: Bacteria do not play a significant role in the production of citric acid; they are more involved in processes like fermentation for dairy products.
- **Option 4: Penicillium**: This is a genus of fungi known for its role in antibiotic production, particularly penicillin, and is not associated with citric acid production.

3. **Identify the Correct Answer**: Based on the evaluation, the most suitable option for the commercial source of citric acid is **Option 2: Aspergillus**.

4. **Conclusion**: Therefore, the correct answer to the question is **Aspergillus**.

### Final Answer:
The commercial source of manufacture of citric acid is **Aspergillus** (Option 2).

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