Which one of the following is wrongly matched?

Options

A. Cassia - Imbricate aestivation
B. Root pressure -Guttation
C. Puceinia- Smut
D. Root-Exarch protoxylem

Answer

To determine which of the following options is wrongly matched, we will analyze each option provided:

1. **Cassia imbricate estivation**:
- **Estivation** refers to the arrangement of petals or sepals in a flower bud before it opens. In Cassia, the estivation is indeed imbricate, meaning the petals or sepals are arranged in a way that they overlap each other in a twisted manner. This option is correctly matched.

2. **Root pressure and guttation**:
- **Root pressure** is a phenomenon that occurs in plants where water is pushed upward from the roots to the stem due to osmotic pressure. **Guttation** is the process where water is exuded from the leaves of a plant, typically at night, due to root pressure. This option is also correctly matched.

3. **Paxinia smut**:
- **Paxinia** is a genus of fungi that belongs to the class **Basidiomycetes**. However, it is primarily known for causing **wheat rust**, not smut. Smut and rust are two different types of fungal diseases. Therefore, this option is wrongly matched.

4. **Root exarch protozylum**:
- In the context of root development, **exarch** refers to the arrangement of xylem in which the protoxylem is located towards the outside of the root. This is a correct description of root structure.

Based on the analysis, the wrongly matched option is **Paxinia smut**.

### Final Answer:
The wrongly matched option is **Paxinia smut**.