Which one of the following is incorrectly matched ?

Options

A. Psilopsida-A fossil member Rhynia
B. Lycopsida-Selaginella
C. Sphenopsida-Adiantum
D. Pteropsida-Dryopteris

Answer

To determine which of the following classes of pteridophytes is incorrectly matched, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understanding Pteridophytes**:
- Pteridophytes are the first terrestrial plants that possess vascular tissues (xylem and phloem). They are divided into several classes.

2. **Identifying the Classes**:
- The classes mentioned are:
- Psilopsida
- Lycopsida
- Sphenopsida
- Pteropsida

3. **Analyzing Each Class**:
- **Psilopsida**: This class includes the genus Rhynia, which is a fossil member. This matching is correct.
- **Lycopsida**: This class includes the genus Selaginella. This matching is also correct.
- **Sphenopsida**: This class is often associated with the genus Equisetum. However, the transcript mentions Adiantum, which is not part of Sphenopsida.
- **Pteropsida**: This class includes the genus Adiantum along with others like Dryopteris and Pteris. This matching is correct.

4. **Identifying the Incorrect Match**:
- The incorrect match is found in the Sphenopsida class, where Adiantum is incorrectly associated. Adiantum belongs to the Pteropsida class.

5. **Conclusion**:
- Therefore, the incorrectly matched option is the third one, which associates Sphenopsida with Adiantum.

### Final Answer:
The incorrectly matched option is **Sphenopsida - Adiantum**.

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