Select the mismatch

Options

A. Frankia - Alnus
B. Rhodospirillum - Mycorrhiza
C. Anabaena - Nitrogen fixer
D. Rhizobium - Alfalfa

Answer

To solve the question of selecting the mismatch from the given pairs, we will analyze each pair one by one to determine if they are correctly matched or not.

### Step-by-Step Solution:

1. **Analyze the first pair: Francia and Alnus**
- **Francia**: A genus of nitrogen-fixing bacteria.
- **Alnus**: A type of actinorhizal plant.
- **Relationship**: Francia lives in symbiosis with Alnus, which is correct.
- **Conclusion**: This pair is correctly matched.

2. **Analyze the second pair: Rhodospirillum and Mycorrhiza**
- **Rhodospirillum**: A type of photosynthetic bacteria.
- **Mycorrhiza**: A mutual symbiotic association between a fungus and a plant.
- **Relationship**: There is no direct relationship between Rhodospirillum and Mycorrhiza.
- **Conclusion**: This pair is a mismatch.

3. **Analyze the third pair: Anabina and nitrogen fixer**
- **Anabina**: A genus of filamentous cyanobacteria known for nitrogen-fixing abilities.
- **Nitrogen fixer**: Refers to organisms that can convert atmospheric nitrogen into a usable form for plants.
- **Relationship**: Anabina is indeed a nitrogen fixer.
- **Conclusion**: This pair is correctly matched.

4. **Analyze the fourth pair: Rhizobium and Alfalfa**
- **Rhizobium**: A genus of bacteria associated with the formation of root nodules in legumes.
- **Alfalfa**: A type of legume that can form a symbiotic relationship with Rhizobium.
- **Relationship**: Rhizobium and Alfalfa have a symbiotic relationship.
- **Conclusion**: This pair is correctly matched.

### Final Conclusion:
The mismatch is found in the pair **Rhodospirillum and Mycorrhiza**.