Choose the odd one w.r.t. cryptogams

Options

A. Chlamydomonas
B. Porphyra
C. Anabaena
D. Spirogyra

Answer

To solve the question of identifying the odd one out with respect to cryptogams, we need to analyze the given options and their classifications.

### Step-by-Step Solution:

1. **Understand Cryptogams**:
- Cryptogams are non-flowering plants that do not have true roots, stems, or leaves. They include organisms such as algae, lichens, and bryophytes.

2. **List the Options**:
- The options provided are Clamidomonas, Porphyra, Anabena, and Spirogyra.

3. **Identify Each Organism**:
- **Clamidomonas**: This is a type of green algae and is classified under cryptogams.
- **Porphyra**: This is also a type of red algae and falls under cryptogams.
- **Anabena**: This is a genus of cyanobacteria (often referred to as blue-green algae). It is not classified as a true plant and does not fall under cryptogams.
- **Spirogyra**: This is a filamentous green algae and is classified under cryptogams.

4. **Determine the Odd One Out**:
- After analyzing the classifications, we see that Clamidomonas, Porphyra, and Spirogyra are all types of algae and are considered cryptogams. However, Anabena is a cyanobacterium and is not classified as a true plant, making it the odd one out.

5. **Conclusion**:
- The odd one out with respect to cryptogams is **Anabena**.