Which of the following is not the belief of an organic farmer?

Options

A. The more variety a landscape has, the more sustainable it is
B. The insects that are sometimes called pests are not eradicated, but instead are kept at manageable levels by a complex system of checks and balances within a living and vibrant ecosystem
C. For controlling plant diseases and pests, chemicals like insecticides and pesticides should be used extensively
D. Eradication of the pests is undersirable because they act as food or hosts for beneficial predatory and parasitic insects

Answer

To solve the question "Which of the following is not the belief of an organic farmer?" we will follow these steps:

### Step 1: Understand Organic Farming
Organic farming is defined as an agricultural practice that avoids the use of artificial and chemical agents, such as fertilizers, pesticides, and insecticides. This is the fundamental principle that guides organic farmers.

### Step 2: Analyze the Statements
We need to evaluate each statement provided in the options to determine which one does not align with the beliefs of organic farmers.

1. **Statement 1**: "The more variety, more variety of landscape has, the more sustainable is it."
- This statement supports biodiversity, which is a key principle in organic farming. Therefore, it is a correct belief.

2. **Statement 2**: "The insects that are sometimes called pests are not eradicated but instead are kept at the manageable level by a complex system of checks and balance with the living and vibrant ecosystem."
- This statement reflects the organic farming philosophy of maintaining ecological balance rather than eliminating pests entirely. Hence, it is also a correct belief.

3. **Statement 3**: "For controlling plant disease and pest chemical like insecticides and pesticides should be used extensively."
- This statement contradicts the principles of organic farming, as organic farmers do not use chemical pesticides and insecticides. Therefore, this is the incorrect belief.

4. **Statement 4**: "The eradication of the pest is undesirable because they act as food or host for the beneficial predatory and parasitic insects."
- This statement aligns with organic farming beliefs, emphasizing the importance of maintaining a balanced ecosystem. Thus, it is a correct belief.

### Step 3: Identify the Incorrect Statement
From the analysis, we can conclude that the statement which does not align with the beliefs of an organic farmer is:
- **Statement 3**: "For controlling plant disease and pest chemical like insecticides and pesticides should be used extensively."

### Final Answer
The correct answer is **Statement 3**.

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