To solve the question regarding which plants have their roots, stems, and leaves modified for the same purpose, we can analyze the options provided step by step.
### Step-by-Step Solution:
1. **Identify the Purpose of Modifications**:
- We need to find plants where the modifications of the roots, stems, and leaves serve the same function. This function could be for support, nutrition, or any other purpose.
2. **Analyze Each Option**:
- **Dollycose**: The stem is modified to become a climber for support. The roots and leaves do not serve the same purpose.
- **Dichos Rhea**: The aerial stems provide growth support. Again, the roots and leaves do not match in purpose.
- **Dionea (Venus flytrap)**: The leaves are modified to catch insects for nutrients, but the roots and stems do not serve the same purpose.
- **Teniophyllum**: The roots are ribbon-like and help in photosynthesis, but the stem and leaves do not match in purpose.
- **Euphorbia**: The stem is modified for photosynthesis, and in Acacia, the leaves are modified into spines which also help in photosynthesis. Here, the modifications of stem and leaves serve the same purpose, but the roots are not mentioned.
- **Asparagus**: The stem is modified into tendrils for climbing. The roots and leaves do not serve the same purpose.
- **Nerium**: This is a parasitic plant. The modifications do not align with a common purpose.
- **Brachyphyllum**: The leaf structure aids in gas exchange, differing from root and stem purposes.
- **Wanda**: An epiphyte that grows on other plants, but the modifications do not align.
- **Citrus**: Produces thorns for defense, not matching the purpose of roots and leaves.
- **Nepenthes (pitcher plant)**: Leaves modified to catch insects, but roots and stems do not serve the same purpose.
3. **Conclusion**:
- After analyzing the options, it appears that Euphorbia and Acacia have modifications that serve the same purpose (photosynthesis) for their stems and leaves. However, the roots were not mentioned in the same context. Therefore, the best option that aligns with the question is **Euphorbia**, where the stem and leaves are modified for photosynthesis.
### Final Answer:
The roots, stem, and leaves are modified for the same purpose respectively in **Euphorbia**.
