Which one is false?

Options

A. Soil supplies minerals, harbours `N_(2)` -fixing bacteria and other microbes, holds water, supplies `O_(2)` to root and acts as matrix that stabilises the plant
B. Both macro and micro nutrients form component of fertilizers
C. Weathering and breaking down of rock enrich the soil with dissolved ions and inorganic salts
D. Dentrification is not the job of bacteria Pseudomonas and Thiobacillus

Answer

To determine which statement is false among the provided options, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Analyze Option 1**:
- **Statement**: "Soil supplies minerals, harbours nitrogen-fixing bacteria and other microbes, holds water, supplies O2 to roots, and acts as a matrix that stabilizes the plant."
- **Evaluation**: This statement is true. Soil indeed plays multiple roles including supplying minerals, providing habitat for bacteria, retaining water, supplying oxygen, and stabilizing plants.

**Hint**: Consider the various functions of soil in supporting plant life.

2. **Analyze Option 2**:
- **Statement**: "Both macro and micronutrient form component of fertilizer."
- **Evaluation**: This statement is also true. Fertilizers typically contain both macronutrients (like nitrogen, phosphorus, potassium) and micronutrients (like zinc, copper).

**Hint**: Recall the different types of nutrients present in fertilizers.

3. **Analyze Option 3**:
- **Statement**: "Weathering and breaking down of rock enters the soil with dissolved iron and inorganic salt."
- **Evaluation**: This statement is true. Weathering of rocks contributes to the soil by adding minerals, including dissolved iron and inorganic salts.

**Hint**: Think about the process of soil formation and the contributions of rock weathering.

4. **Analyze Option 4**:
- **Statement**: "Denitrification is not the job of bacteria, pseudomonas and theobacillus."
- **Evaluation**: This statement is false. Denitrification is indeed carried out by bacteria such as Pseudomonas and Thiobacillus, which convert nitrates into atmospheric nitrogen.

**Hint**: Remember the role of specific bacteria in the nitrogen cycle, especially in denitrification.

### Conclusion:
The false statement is **Option 4**, as denitrification is indeed the job of bacteria like Pseudomonas and Thiobacillus.

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