资料：The market is a concept. If you are growing tomatoes in your backyard for sale you are producing for the market. You might sell some to your neighbor and some to the local manager of the supermarket. But in either case, you are producing for the market. Your efforts are being directed by the market. If people stop buying tomatoes, you will stop producing them.
If you take care of a sick person to earn money, you are producing for the market. If your father is a steel worker or a truck driver or a doctor or a grocer, he is producing goods or service for the market.
When you spend your income, you are buying things from the market. You may spend money in stores, supermarkets, gas stations and restaurants. Still you are buying from the market. When the local grocer hires you to drive the delivery truck, he is buying your labor in the labor market.
The market may be something abstract. But for each person or business that is making and selling something, it is very concrete. If nobody buys your tomatoes, it won’t be long before you get the message. The market is telling you something. It is telling you that you are using energies and resources in doing something the market doesn’t want you to do.
The word “concrete”in the last paragraph may most probably mean____.
本题考查的是判断推理。
【关键词】concrete
【主题句】But for each person or business that is making and selling something, it is very concrete. 但是对一个人或商业活动来说，市场就是制造和销售东西，是非常实在的。
【解析】题目意为“文章最后一段中的concrete一词最可能意为____”，选项A意为“严重的、严肃的”，选项B意为“正确的”，选项C意为“重要的”，选项D意为“实在的”。根据文章最后一段，D选项符合题意。
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由此可推断出（）
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