Which is not true for monocot stem ?

Options

A. (a) Sclerenchymatous hypodermis
B. (b) Presence of water cavity in pith
C. (c) Conjoint collateral closed vascular bundles
D. (d) Presence of bundle sheath

Answer

To determine which statement is not true for monocot stems, we will evaluate each option provided in the question step by step.

### Step-by-Step Solution:

1. **Understanding Monocot Stems**:
- Monocot stems have distinct anatomical features that differentiate them from dicot stems. Key characteristics include the arrangement of vascular bundles, the type of hypodermis, and the presence or absence of certain structures.

2. **Evaluating Option A - Sclerenchymatous Hypodermis**:
- In monocot stems, the hypodermis is typically made up of sclerenchyma, which provides strength and support. This statement is true.

3. **Evaluating Option B - Presence of Water Cavity in PIT**:
- The term "PIT" refers to the presence of intercellular spaces or cavities. In monocot stems, vascular bundles are scattered, and they do not have water cavities. This statement is false, making it the incorrect option.

4. **Evaluating Option C - Conjoined Collateral Closed Vascular Bundles**:
- Monocot stems contain vascular bundles that are conjoined (phloem and xylem are together), collateral (phloem is on the outside and xylem is on the inside), and closed (no cambium present). This statement is true.

5. **Evaluating Option D - Presence of Bundle Sheath**:
- Bundle sheaths are present in monocot stems, providing protection to the vascular bundles. This statement is also true.

6. **Conclusion**:
- After evaluating all options, we find that option B is the only statement that is not true for monocot stems. Therefore, the answer to the question is option B.

### Final Answer:
**B - Presence of water cavity in PIT is not true for monocot stem.**