To determine which flowers have a half-inferior ovary, we need to understand the classification of flowers based on the position of their ovary in relation to other floral parts (calyx, corolla, and androsium).
### Step-by-Step Solution:
1. **Understand Flower Structure**: Flowers can be classified based on the position of the ovary. The three main types are hypogynous, perigynous, and epigynous.
2. **Identify Hypogynous Flowers**: In hypogynous flowers, the ovary is superior, meaning it is positioned above the other floral parts. Examples include mustard, China rose, and brinjal.
3. **Identify Perigynous Flowers**: In perigynous flowers, the ovary is half-inferior. This means the ovary is situated in the center, with other floral parts located around it at the same level. Examples of this type include plum, peach, and rose.
4. **Identify Epigynous Flowers**: In epigynous flowers, the ovary is inferior, meaning it is located below the other floral parts. The thalamus grows upwards to enclose the ovary. Examples include guava and cucumber.
5. **Conclusion**: Since the question specifically asks for flowers with a half-inferior ovary, the correct answer is the flowers that fall under the perigynous category, which includes plum, peach, and rose. Therefore, the right answer is option number two.
### Final Answer:
The ovary is half-inferior in the flowers of **plum, peach, and rose** (option number two).
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