Choose the correct option Mycorrhiza is a symbiotic association of fungus with root system which helps in
`A`. absorption of water
`B`. mineral nutrition
`C.` translocation
`D`.gaseous exchange.

Options

A. Only`A`
B. Only`B`
C. Both `A` and `B`
D. Both `B` and `C`

Explanation

To solve the question regarding the role of mycorrhiza in plants, let's break it down step by step:

### Step-by-Step Solution:

1. **Understanding Mycorrhiza**: Mycorrhiza is a symbiotic association between fungi and the roots of higher plants. This relationship is mutualistic, meaning both the fungus and the plant benefit from it.

2. **Function of Mycorrhiza**: The primary function of mycorrhiza is to enhance the plant's ability to absorb water and nutrients from the soil. The fungal hyphae extend the root system's reach, allowing for greater absorption.

3. **Absorption of Water**: The mycorrhizal fungi increase the surface area of the root system, which significantly improves the plant's capacity to absorb water from the soil.

4. **Mineral Nutrition**: In addition to water, mycorrhizae also help in the absorption of essential minerals (like phosphorus, nitrogen, and potassium) that are crucial for plant growth.

5. **Evaluating Options**:
- Option A: Absorption of water - Correct
- Option B: Mineral nutrition - Correct
- Option C: Translocation - Not directly related to mycorrhiza
- Option D: Gaseous exchange - Not related to mycorrhiza

6. **Choosing the Best Option**: Since both options A (absorption of water) and B (mineral nutrition) are correct, the best choice is the option that includes both A and B.

### Final Answer:
The correct option is **both A and B**.