Find the mis-match

Options

A. Conjoint vascular bundles -phloem on different radii
B. Closed Vascular Bundles-Cambium is absent
C. Xylem and Radial Vascular Bundles-Xylem and Phloem on different radii
D. Dicotyledonous stem - Cambium is present

Answer

To find the mismatch among the given options regarding vascular bundles, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Understanding Co-joint Vascular Bundles**:
- Co-joint vascular bundles are characterized by the presence of both xylem and phloem located at the same radius from the center of the stem.
- **Mismatched Statement**: The option states that in co-joint vascular bundles, xylem and phloem are at different radii. This is incorrect because they are actually at the same radius.

2. **Analyzing Closed Vascular Bundles**:
- Closed vascular bundles are those where the cambium is absent, and the xylem and phloem are surrounded by sclerenchyma.
- **Correct Statement**: The option states that cambium is present in closed vascular bundles. This is incorrect; thus, this statement is also a mismatch.

3. **Examining Radial Vascular Bundles**:
- In radial vascular bundles, xylem and phloem are located at different radii from the center, which is a true statement.
- **Correct Statement**: The option correctly states that in radial vascular bundles, xylem and phloem are at different radii.

4. **Considering Dichotyledonous Stem**:
- In a dichotyledonous stem, cambium is present, allowing for secondary growth.
- **Correct Statement**: The statement regarding the presence of cambium in a dichotyledonous stem is true.

5. **Identifying the Mismatch**:
- After analyzing all options, the first option regarding co-joint vascular bundles is the only one that is incorrect. The correct information should state that xylem and phloem are at the same radius, not different.

### Conclusion:
The mismatch is found in the first option regarding co-joint vascular bundles, which incorrectly states that xylem and phloem are at different radii.

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