听力原文：Wild carrots probably evolved with the other flowering plants, about 360 million years ago. Like apples, carrots are native to Central Asia. That's why horses, which also come from Central Asia, like both apples and carrots so much.
    [16]Root wild carrots, the roots are white, small and skinny, so you have to pick a lot of wild carrots to get enough to eat. Doctors used carrot seeds and roots as medicine, on the theory that foods that taste bad must be good for you.
    Around 800 AD, people in Central Asia managed to develop a new kind of carrot—a purple carrot— that attracted more interest from international traders. [l7]Then in the late 1500s, food scientists in the Netherlands cultivated large, straight, sweet, red carrots like the ones we eat today. But people still mostly fed carrots to horses and donkeys and pigs, and didn't eat them themselves.
In the 1600s, people in China used carrots as medicine, but they also ate carrots boiled in soup. The red color was popular for Chinese New Year celebrations.
    [18]But carrots got their biggest boost during the two World Wars, when food shortages forced people to eat them, and governments told everyone how healthy carrots were. Today, cooler countries grow most of the world's carrots. Machines do most of the planting and picking, and carrots are easy to store and ship, so they are cheap almost everywhere.
16. What do we learn from the talk about wild carrots?
17. What does the speaker say about carrots in the late 1500s?
18. Why did people turn to carrots for food during the two world wars?

解析：题目问的是我们可以从讲座中了解到胡萝卜的什么信息。录音提到，胡 萝卜的根部是白色的，很小很细，故选 A“胡萝卜的根部很小。”

题目问的是关于 16 世纪末的胡萝卜， 说话人提及了什么信息。录音中提到，在 16 世纪末，荷兰的科学家培育出了笔直的、甜昧 的大棵红色胡萝卜，就像我们今天所食用的一样，故选 D“它们开始跟现代的胡萝卜长得一 样”。

题目问的是在两次世界大战中，为 什么人们把胡萝卜转变为食物。录音提到。在两次世界大战中，由于食物短缺，迫使人们开 始食用胡萝卜，故选 B“由于严重的食物短缺”。