Which one is not matched

Options

A. Streptomyces- Antibiotic
B. Serratia- Drug addiction
C. Rhizobium -Biofertilizer
D. Spirulina-Single cell protein.

Answer

To determine which option is not correctly matched, we will analyze each option provided in the question step by step.

### Step 1: Analyze the first option - Streptomyces and Antibiotic
- **Streptomyces** is a genus of bacteria known for its ability to produce antibiotics.
- It is indeed a gram-positive bacterium and is one of the largest bacterial genera that produce various antibiotics.
- **Conclusion**: This pair is correctly matched.

### Step 2: Analyze the second option - Serratia and Drug Addiction
- **Serratia** is a genus of bacteria that can act as a human pathogen, causing infections such as urinary tract infections (UTIs) and wound infections.
- However, it is not associated with drug addiction.
- **Conclusion**: This pair is incorrectly matched, making it a candidate for the answer.

### Step 3: Analyze the third option - Rhizobium and Biofertilizer
- **Rhizobium** is a type of soil bacteria that forms a symbiotic relationship with the roots of legumes, fixing nitrogen and providing it to the plants.
- It is indeed used as a biofertilizer due to its role in enhancing soil fertility.
- **Conclusion**: This pair is correctly matched.

### Step 4: Analyze the fourth option - Spirulina and Single Cell Protein
- **Spirulina** is a type of blue-green algae (cyanobacteria) that is rich in protein and is often consumed as a dietary supplement.
- It is recognized as a source of single-cell protein due to its high protein content.
- **Conclusion**: This pair is correctly matched.

### Final Conclusion
After analyzing all options, the only pair that is not correctly matched is **Serratia and Drug Addiction**. Therefore, the correct answer is option 2.

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