Most primitive members in which roots not present in
Or
Which of the following is a fossil pteridophyte
(a) Psilotum
(b) Rhynia
(c) Lycopodium
(d) Selaginella

Options

A. Psilotum
B. Rhynia
C. Lycopodium
D. Selaginella.

Explanation

To solve the question regarding which of the following is a fossil pteridophyte, we will analyze each option provided.

### Step-by-Step Solution:

1. **Understanding the Question**:
The question asks for a fossil pteridophyte and mentions that it is primitive and lacks true roots.

2. **Analyzing the Options**:
- **(a) Psilotum**: This is a living genus of pteridophytes known as whisk ferns. It has some root-like structures but is not considered a fossil.
- **(b) Rhynia**: This is a well-known fossil pteridophyte from the Devonian period. It is primitive and indeed lacks true roots, making it a suitable candidate.
- **(c) Lycopodium**: This is a living genus of clubmosses, not a fossil, and it has true roots.
- **(d) Selaginella**: This is another living genus of pteridophytes known as spike mosses, which also have true roots.

3. **Identifying the Correct Answer**:
Based on the analysis, Rhynia is the only option that fits the criteria of being a fossil pteridophyte that is primitive and lacks true roots.

### Conclusion:
The correct answer is **(b) Rhynia**.

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