Which one of the following is not characteristic of all divisions of vascular plants?

Options

A. (a) An alternation of generations
B. (b) The development of seeds
C. (c) Differentiation into roots, stems and leaves
D. (d) Xylem and phloem for transporting materials between roots and leaves.

Answer

To determine which characteristic is not common to all divisions of vascular plants, we can analyze the options provided based on the known features of vascular plants.

### Step-by-Step Solution:

1. **Understand Vascular Plants**: Vascular plants, also known as tracheophytes, are characterized by the presence of specialized tissues for conducting water (xylem) and nutrients (phloem).

2. **Identify the Divisions of Vascular Plants**: The main divisions of vascular plants include:
- Pteridophytes (ferns and their relatives)
- Gymnosperms (naked seed plants)
- Angiosperms (flowering plants)

3. **Analyze Each Option**:
- **Option A: Alteration of Generations**: This is a common feature in all vascular plants. Both haploid (gametophyte) and diploid (sporophyte) generations are present in pteridophytes, gymnosperms, and angiosperms.
- **Option B: Development of Seeds**: This characteristic is not present in pteridophytes, which do not produce seeds. Seeds are found in gymnosperms and angiosperms.
- **Option C: Differentiation into Roots, Stems, and Leaves**: All vascular plants exhibit this feature, as they have a well-defined structure.
- **Option D: Presence of Xylem and Phloem**: This is a defining characteristic of all vascular plants.

4. **Conclusion**: Since the development of seeds is not a characteristic of pteridophytes, which lack seeds, the correct answer to the question is **Option B: Development of Seeds**.

### Final Answer:
**B: Development of Seeds**