In dicot stem

Options

A. Vascular bundles are conjoint, open and arranged in a ring
B. Xylem is endarch
C. Collenchymatous hypodermis
D. All

Answer

### Step-by-Step Solution:

1. **Understanding the Structure of Dicot Stem**:
- In dicot stems, the vascular bundles are an essential part of the plant's anatomy. They consist of xylem and phloem, which are crucial for the transport of water, nutrients, and food.

2. **Arrangement of Vascular Bundles**:
- In dicot stems, the vascular bundles are arranged in a ring formation. This is a distinctive feature that differentiates dicots from monocots, where vascular bundles are scattered.

3. **Type of Vascular Bundles**:
- The vascular bundles in dicot stems are described as "conjoined" and "open". This means that the xylem and phloem are present together in each bundle and that there is the potential for secondary growth due to the presence of cambium.

4. **Xylem Arrangement**:
- Within the vascular bundles, the xylem is arranged in a specific manner. The protoxylem (the first formed xylem) is located towards the center, while the metaxylem (the later formed xylem) is found towards the periphery. This arrangement is referred to as "endark".

5. **Hypodermis Composition**:
- The hypodermis of the dicot stem is made up of collenchyma cells. These cells provide support and flexibility to the stem, allowing it to withstand various stresses.

6. **Conclusion**:
- Based on the above points, all the statements regarding the dicot stem are correct. Therefore, the correct answer to the question is option 4, which states that all the mentioned features are present in the dicot stem.