Monochasial pattern is found in the inflorescence of
I) Leucas II) Euphorbia
III) Ficus IV) Hamelia

Options

A. IV only
B. I, II and III
C. I, III and IV
D. I, II and IV

Answer

To determine which plants exhibit a monocasial pattern in their inflorescence, we need to analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understand Monocasial Pattern**:
- A monocasial pattern refers to a type of inflorescence where the flowers are arranged in a single branch on one side of the main axis. This means that the branching occurs only on one side, leading to a unilaterally arranged flower structure.

2. **Evaluate Each Plant**:
- **I) Leucas**:
- The inflorescence of Leucas exhibits a monocasial pattern. The branches grow on one side only, confirming that this plant fits the criteria.

- **II) Euphorbia**:
- Euphorbia also shows a monocasial pattern in its inflorescence. The flowers, which are often referred to as false flowers, form from bracts and are arranged unilaterally.

- **III) Ficus**:
- Ficus does not exhibit a monocasial pattern. Instead, it has a dicasial pattern where the branches are arranged on both sides of the main axis, which disqualifies it from being part of the monocasial group.

- **IV) Hamelia**:
- Hamelia displays a monocasial pattern in its inflorescence as well. Similar to Leucas and Euphorbia, the branching occurs on one side.

3. **Conclusion**:
- Based on the analysis, the plants that exhibit a monocasial pattern are **Leucas (I)**, **Euphorbia (II)**, and **Hamelia (IV)**. Therefore, the correct answer is options I, II, and IV.

### Final Answer:
The plants that exhibit a monocasial pattern in their inflorescence are **I) Leucas, II) Euphorbia, and IV) Hamelia**.

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