A、To protect animals from being eaten. B、To find out a healthier way of eating meat. C、To show the health effects of being veget

(23)If you stop eating meat, your food-related carbon footprint could drop sharply to less than half of what it was. That is a much bigger drop than many previous estimates, and it comes from a study of people’s real diets. As much as a quarter of our greenhouse gas emissions come from food production. But it’s not clear how much would really be saved if people swapped their beef steaks for vegetables. On some estimates, going vegetarian could cut out 25 per cent of your diet-related emissions. But it all depends on what you eat instead of the meat.(24)So Peter Scarborough and his colleagues at the University of Oxford took data on the real diets of more than 50 000 people in the UK, and calculated their diet-related carbon footprints. "This is the first paper to confirm and quantify the difference," says Scarborough. They found that the benefits could be huge. If someone eating more than 100 grams of meat a day simply cut down to less than 50 grams a day, their food-related emissions would fall by a third. That would save almost a tonne of CO₂ each year, about as much as an economy return flight between London and New York. "In general there is a clear and strong trend with reduced greenhouse gas emissions in diets that contain less meat," says Scarborough. There are other ways of reducing emissions, such as driving and flying less, but changing food habits will be easier for many, says Scarborough.(25)"I think it is easier to change your diet than to change your travel behaviour, but others may not agree."
23. What will happen if people stop eating meat according to the speaker?
24. What is the purpose of the study?
25. What is Scarborough’s opinion on the ways of reducing emissions?