The stems of hydrophytic plants are soft and weak because of the poor development of

Options

A. Pith and supporting parencyma
B. Phloem and comanion cells
C. Xylem and suppoting tissue
D. Cortex and endodermis

Answer

To answer the question about why the stems of hydrophytic plants are soft and weak, we need to analyze the role of various plant tissues and their development in these types of plants.

### Step-by-Step Solution:

1. **Understanding Hydrophytic Plants**:
- Hydrophytic plants are those that grow in water or in very moist environments. They have adapted to these conditions, which affects their structural features.

2. **Identifying the Key Features of Stems**:
- The stems of these plants are typically soft and weak compared to those of terrestrial plants. This is primarily due to the lack of certain supportive structures.

3. **Role of Xylem**:
- Xylem is a type of vascular tissue responsible for the conduction of water and minerals from the roots to the rest of the plant. It also plays a crucial role in providing mechanical support due to the presence of lignin in its cell walls.

4. **Secondary Growth**:
- Secondary growth refers to the increase in girth of the plant stems and roots, which is primarily facilitated by the formation of secondary xylem (wood). In many terrestrial plants, this growth is essential for structural support.

5. **Poor Development of Xylem in Hydrophytes**:
- In hydrophytic plants, the xylem is often poorly developed. This is because these plants do not require as much structural support or water conduction capacity due to their aquatic environment, where water is readily available.

6. **Conclusion**:
- As a result of the poor development of xylem and supporting tissues, the stems of hydrophytic plants remain soft and weak. Therefore, the correct answer to the question is that the stems are soft and weak because of the poor development of **xylem and supporting tissue**.

### Final Answer:
The stems of hydrophytic plants are soft and weak because of the poor development of **xylem and supporting tissue**.