Read the following passage and answer the item that follows. Your answer to this item should be based on the passage only.

The newly released oilseed variety 'Suraksha Mustard 9' can be grown across the mustard belts of Rajasthan, Haryana and Madhya Pradesh, and eventually across most of India's rabi-cropping regions. Its yield, about 2,200 kg/hectare, is significantly higher than existing varieties, and because its pod size is uniform, it is well suited to mechanical harvesting, an attractive feature for farmers in northern India who already use this technology for wheat. Most importantly, its stalk decomposes quickly once ploughed back, unlike the stalk of the variety it replaces, which farmers usually just burn.

Which of the following are the most rational inferences that can be made from the passage?

1. Farmers' income will be higher with this variety than with the variety it replaces.

2. Switching to this variety causes less stubble burning than the variety it replaces.

3. This variety's stalk can be used to improve soil quality.

4. In the context of northern Indian agriculture, the old mustard variety's stalk has no usefulness at all.

5. Mechanised agriculture is the main cause of stubble burning.

Select the correct answer using the code given below.