A: Prop roots are rope like showing oblique growth.
R:Prop roots are adventitious roots for extra-support and assimilation.

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that "Prop roots are rope-like showing oblique growth."
- Prop roots are indeed rope-like structures that emerge from the stem of certain plants, particularly in mangroves.
- However, the term "oblique growth" is misleading. Prop roots typically grow vertically downwards to provide support to the plant.

2. **Evaluating the Assertion**:
- Since prop roots do not show oblique growth but rather vertical growth, the assertion is **incorrect**.

3. **Understanding the Reason (R)**:
- The reason states that "Prop roots are adventitious roots for extra support and assimilation."
- It is true that prop roots are adventitious roots and they provide extra support to the plant.
- However, the term "assimilation" usually refers to the process of absorption and utilization of nutrients. Prop roots are primarily for support and do not play a significant role in assimilation.

4. **Evaluating the Reason**:
- While the part about providing extra support is correct, the mention of assimilation is incorrect. Therefore, the reason is **partially incorrect**.

5. **Conclusion**:
- Since the assertion is incorrect and the reason is also incorrect (due to the misunderstanding of assimilation), we conclude that both statements are incorrect.

### Final Answer:
Both the assertion (A) and the reason (R) are incorrect.

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