Following pair of the organism are used for antibiotic production:

Options

A. Trichoderma and Monascus
B. Aspergillus niger and Penicillium notatum
C. Lactobacillus and Nucleopolyhedrovirus
D. Baculovirus and Streptococcus

Answer

To solve the question regarding the pair of organisms used for antibiotic production, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understanding the Organisms**:
- **Trichoderma**: This is a genus of fungi known primarily for its role in producing fungicides, not antibiotics.
- **Monascus**: This is a yeast used for lowering blood cholesterol levels, not for antibiotic production.

**Conclusion**: The pair Trichoderma and Monascus is not used for antibiotic production.

2. **Analyzing the Second Pair**:
- **Aspergillus niger**: This fungus is known for producing citric acid and also has some antibiotic properties. It produces Helvolic acid, which is effective against gram-positive bacteria.
- **Penicillium notatum**: This is the source of penicillin, one of the first antibiotics discovered and widely used to treat bacterial infections.

**Conclusion**: The pair Aspergillus niger and Penicillium notatum is indeed used for antibiotic production.

3. **Examining the Third Pair**:
- **Lactobacillus**: This is a genus of bacteria used in the fermentation of milk and is not known for antibiotic production.
- **Nucleopolyhedrovirus**: This is a virus used in pest control and is not related to antibiotics.

**Conclusion**: The pair Lactobacillus and Nucleopolyhedrovirus is not used for antibiotic production.

4. **Evaluating the Fourth Pair**:
- **Baculovirus**: Similar to the previous pair, this virus is primarily used in pest control and does not produce antibiotics.
- **Streptococcus**: While some species can produce substances with antibiotic properties, they are not primarily known for antibiotic production in the same way as Penicillium.

**Conclusion**: The pair Baculovirus and Streptococcus is not used for antibiotic production.

5. **Final Conclusion**:
After evaluating all the options, the only pair of organisms used for antibiotic production is **Aspergillus niger and Penicillium notatum**.

### Answer:
The correct answer is **Aspergillus niger and Penicillium notatum**.

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