从每题A、B、C、D四个选项中，选出一个能回答所提问题或完成所给句子的最佳答案。
Walk or drive to work? Which way is lower in carbon(碳)? To be friendly to the environment, you may choose to walk. Have you ever tried to live a low-carbon life through your diet (日常饮食)?
A new study from the University of Oxford has looked into the health and environmental influences of 15 foods common in western diets. Among these, plant based (基于植物的) foods included fruits, vegetables, nuts and potatoes. It also studied animal-based foods, including red meat, chicken, milk products, eggs and fish.
According to the study's lead researcher, Michael Clark, "Choosing better and greener diets is one of the main ways people can improve their health and protect the environment. "That is to say, plant-based diets are much healthier for us and kinder to the environment.
To get this result, researchers compared the influence of eating another portion (一份) of each food with the increased risk of a few illnesses. They also found out the environmental harm for each animal-based food and each plant-based food.
By using this method, the study found that red meats were the most unfriendly foods to the environment. Keeping farm animals produces a large number of methane (甲烷) that keeps 30 times more heat than CO2. As well as making the earth warmer, eating too much red meat is known to increase the risk of a few illnesses, such as heart trouble.
Plant-based diets can give us the same health benefits in a much greener way. According to the study, without eating or using meat and milk products, global farmland use could be cut down by more than 75% and still feed the world.
Speaking to the Guardian(英国卫报), Tim Benton of Chatham House(英国皇家国际事务研究所) said, "If we can give people reasonable official(官方的)advice of what a healthy and green diet is, the world and its people would be in a much better place. "
