Root-fungal association is called:

Options

A. Lichen
B. Mycorrhiza
C. Parasitism
D. Amensalism

Answer

To answer the question "Root-fungal association is called:", we will analyze the options provided and identify the correct term for this association.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the specific term used to describe the association between roots and fungi.

2. **Analyzing the First Option - Lichen**:
- Lichen is a symbiotic relationship between two different organisms: algae and fungi.
- In lichen, both organisms benefit from each other, which is known as mutualism.
- However, since lichen does not specifically refer to a root-fungal association, this option is incorrect.

3. **Analyzing the Second Option - Mycorrhiza**:
- Mycorrhiza refers to a symbiotic association specifically between fungi and the roots of higher plants.
- In this relationship, both the fungi and the plant benefit from each other. The fungi help the plant absorb water and nutrients, while the plant provides carbohydrates to the fungi.
- This is indeed a root-fungal association, making this option correct.

4. **Analyzing the Third Option - Parasitism**:
- Parasitism is a relationship where one organism benefits at the expense of another, which is harmed.
- In this case, the host organism is negatively affected, making this option incorrect for root-fungal associations.

5. **Analyzing the Fourth Option - Amensalism**:
- Amensalism is a relationship where one organism is harmed (denoted by a negative sign), and the other is unaffected (denoted by a zero sign).
- This does not apply to root-fungal associations, making this option incorrect as well.

6. **Conclusion**: Based on the analysis, the correct answer to the question "Root-fungal association is called:" is **Mycorrhiza**.

### Final Answer:
Root-fungal association is called **Mycorrhiza**.

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