Among the following , secondary growth is seen in a-dicot root, b-dicot stem, c-monocot root, d-monocot stem, e-gymnosperm root, f-gymnosperm stem

Options

A. a,b,c and d
B. c,d,e andf
C. a,b,e and f
D. All of the above

Explanation

To determine where secondary growth occurs among the given options, we need to analyze each one based on the presence of cambium and the type of plant.

### Step-by-Step Solution:

1. **Understand Secondary Growth**:
- Secondary growth refers to the increase in thickness or girth of the plant due to the formation of secondary tissues, primarily secondary xylem and secondary phloem.
- This growth is facilitated by the cambium, a layer of meristematic tissue.

2. **Analyze Each Option**:
- **Option A: Dicot Root**:
- Dicot roots have a cambium formed from the paricycle, which allows for secondary growth.
- **Conclusion**: Yes, secondary growth occurs.

- **Option B: Dicot Stem**:
- In dicot stems, vascular bundles are arranged in a ring with cambium present between them, allowing for secondary growth.
- **Conclusion**: Yes, secondary growth occurs.

- **Option C: Monocot Root**:
- Monocot roots do not have a cambium; hence, they do not undergo secondary growth.
- **Conclusion**: No, secondary growth does not occur.

- **Option D: Monocot Stem**:
- Monocot stems have closed vascular bundles without cambium, which means they do not have secondary growth.
- **Conclusion**: No, secondary growth does not occur.

- **Option E: Gymnosperm Root**:
- Gymnosperms, like dicots, have cambium and can undergo secondary growth.
- **Conclusion**: Yes, secondary growth occurs.

- **Option F: Gymnosperm Stem**:
- Similar to gymnosperm roots, gymnosperm stems also have cambium and can develop secondary growth.
- **Conclusion**: Yes, secondary growth occurs.

3. **Final Conclusion**:
- Secondary growth is observed in:
- Dicot Root (A)
- Dicot Stem (B)
- Gymnosperm Root (E)
- Gymnosperm Stem (F)
- Therefore, the options that exhibit secondary growth are A, B, E, and F.

### Answer:
The correct options where secondary growth occurs are:
- A (Dicot Root)
- B (Dicot Stem)
- E (Gymnosperm Root)
- F (Gymnosperm Stem)