Read the given paragraph where few words have been italicised.
Preparation of soil in a field, before sowing of seeds involves two steps : broadcasting and levelling. Soil in the crop field is enriched with nutrients by adding manures and fertilisers to it. Crop fields need to be irrigated, from time to time. In sprinkler system of irrigation water is allowed to fall drop by drop from a pipe just near the plant roots whereas in drip irrigation water escapes from a revolving nozzle. Weeding in crop fields can be done using combine. After the crop is harvested, the grain is separated from cut crop using a machine called thresher.
Select the incorrect option regarding these.

Options

A. Broadcasting should be replaced by tilling.
B. Positions of sprinkler system and drip irrigation should be interchanged.
C. Thresher should not be replaced as it is correctly mentioned.
D. Combine should be replaced by harvester.

Explanation

To solve the question, we need to identify the incorrect statement regarding the processes and equipment mentioned in the paragraph. Let's break it down step by step:

### Step 1: Understand the Key Terms
- **Broadcasting** and **Levelling**: These are the two steps mentioned for soil preparation before sowing seeds.
- **Manures and Fertilisers**: These are added to enrich the soil with nutrients.
- **Irrigation**: The paragraph mentions two systems - **Sprinkler** and **Drip Irrigation**.
- **Weeding**: This can be done using a **Combine**.
- **Thresher**: This machine is used to separate grain from the harvested crop.

### Step 2: Analyze Each Statement
1. **Broadcasting can be replaced by tilling**: This statement is incorrect. Broadcasting is a method of sowing seeds, while tilling refers to preparing the soil. They are not interchangeable.

2. **The position of the sprinkler system and the drip irrigation should be interchanged**: This statement is incorrect. The sprinkler system allows water to fall near the plant roots, while drip irrigation delivers water drop by drop. They serve different purposes and cannot be interchanged.

3. **The thresher cannot be replaced as it is correctly mentioned**: This statement is correct. The thresher is specifically designed to separate grain from the cut crop.

4. **The combine should be replaced by harvester**: This statement is also incorrect. A combine is a type of harvester that performs multiple functions, including cutting and threshing.

### Step 3: Identify the Incorrect Option
After analyzing the statements:
- The first and second statements are incorrect, but the question asks for the incorrect option regarding the processes and equipment mentioned in the paragraph. The most relevant incorrect statement is about the **combine** and **harvester**, as it is a direct misrepresentation of the equipment.

### Conclusion
The incorrect option regarding the processes and equipment mentioned in the paragraph is that the **combine should be replaced by harvester**.

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