Which pteridophtye has the maximum chromosome number?

Options

A. Ophioglossum reticulatum
B. Azolla pinnata
C. Lycopodium cernuum
D. Selaginella apus

Answer

To determine which pteridophyte has the maximum chromosome number among the given options, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Pteridophytes**: The question provides four pteridophytes to consider:
- Ophioglossum reticulatum
- Azolla pinnata
- Lycopodium sarnum
- Selaginella apus

2. **Research Chromosome Numbers**: We need to find the chromosome numbers for each of these pteridophytes:
- **Ophioglossum reticulatum**: This species has a chromosome number of 1260.
- **Azolla pinnata**: This species has a chromosome number of 88 (or 44 pairs).
- **Lycopodium sarnum**: This species has a chromosome number of 114.
- **Selaginella apus**: This species has a chromosome number ranging from 4 to 36 (or 18 pairs).

3. **Compare the Chromosome Numbers**: Now, we compare the chromosome numbers obtained:
- Ophioglossum reticulatum: 1260
- Azolla pinnata: 88
- Lycopodium sarnum: 114
- Selaginella apus: 4 to 36

4. **Determine the Maximum**: From the comparison, it is clear that Ophioglossum reticulatum has the highest chromosome number of 1260.

5. **Conclusion**: Therefore, the pteridophyte with the maximum chromosome number is **Ophioglossum reticulatum**.

### Final Answer:
The pteridophyte with the maximum chromosome number is **Ophioglossum reticulatum**.

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