All given factors promote absorption of water by roots , except

Options

A. Well aerated soil
B. Highly concentrated soil solution
C. Optimum soil temperature
D. Available water in soil

Answer

To solve the question "All given factors promote absorption of water by roots, except," we need to analyze the options provided and understand how each factor influences water absorption in plants.

### Step-by-Step Solution:

1. **Understanding Water Absorption in Roots**:
- Water absorption in roots is influenced by several factors, including soil concentration, temperature, porosity, and humidity.

2. **Analyzing Each Option**:
- **Option A: Well Irrigated Soil**:
- Well-irrigated soil provides sufficient moisture, promoting water absorption. This factor supports absorption.

- **Option B: Highly Concentrated Soil Solution**:
- A highly concentrated soil solution means that there are more solutes in the soil compared to the roots. This creates a hypertonic environment, causing water to move out of the roots (which are hypotonic) into the soil. Therefore, this factor does not promote absorption; rather, it inhibits it.

- **Option C: Optimum Soil Temperature**:
- An optimum soil temperature enhances metabolic activities and promotes water absorption by roots. This factor supports absorption.

- **Option D: Available Water in Soil**:
- The presence of available water in the soil is crucial for absorption. More water availability means better absorption by the roots. This factor supports absorption.

3. **Conclusion**:
- Among the options, the only factor that does not promote absorption of water by roots is **Option B: Highly Concentrated Soil Solution**.

### Final Answer:
The correct answer is **Option B: Highly Concentrated Soil Solution**.

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