Scaly bark occurs in
(a) eucalyptus
(b) betula
(c) psidium
(d) tectona

Options

A. eucalyptus
B. betula
C. psidium
D. tectona

Answer

To determine which plant has scaly bark, we can analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understand the Concept of Scaly Bark:**
- Scaly bark is a type of bark characterized by its discontinuous nature, which is due to the presence of overlapping periderms. This results in patches of bark on the stem, as some of the bark has been shed.

2. **Analyze Each Option:**
- **(a) Eucalyptus:** This plant is known for having scaly bark due to the overlapping periderms. The bark sheds in patches, leading to the characteristic scaly appearance.
- **(b) Betula (Birch):** Birch trees have a more continuous bark that peels in thin layers but does not exhibit the scaly bark characteristic.
- **(c) Psidium (Guava):** Guava trees generally have smooth bark and do not exhibit the scaly bark feature.
- **(d) Tectona (Teak):** Teak trees have a more continuous and fibrous bark, lacking the scaly appearance.

3. **Conclusion:**
- Based on the analysis, the plant that exhibits scaly bark is **(a) Eucalyptus**.

### Final Answer:
The correct answer is **(a) eucalyptus**.

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