The example of a partial root parasite is

Options

A. Santalum
B. Cuscuta
C. Arceuthobium
D. Viscum

Answer

To determine the example of a partial root parasite from the given options, we will analyze each option based on the definitions and characteristics of partial root parasites.

### Step-by-Step Solution:

1. **Understanding Partial Root Parasites**:
- Partial root parasites, also known as semi-parasites, are plants that derive some of their nutrients from the host plant but can also perform photosynthesis. They typically attach to the roots of their host plants.

2. **Analyzing the Options**:
- **Option A: Centellum (Centellum album)**: This is known as the sandalwood tree and is recognized as a partial root parasite. It attaches to the roots of other plants, such as Dalbergia and Eucalyptus, and derives nutrients while also being capable of photosynthesis.

- **Option B: Cascata**: This plant is a total stem parasite, meaning it relies entirely on its host for nutrients and does not perform photosynthesis.

- **Option C: Archaeothobium**: This is classified as a total root parasite, which means it completely depends on its host for nutrients and does not photosynthesize.

- **Option D: Viscum**: This is also a stem parasite and does not qualify as a partial root parasite.

3. **Conclusion**:
- After analyzing all the options, the only plant that qualifies as a partial root parasite is **Centellum album** (sandalwood tree). Therefore, the correct answer is **Option A: Centellum**.

### Final Answer:
The example of a partial root parasite is **Centellum album** (sandalwood tree).

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