Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the questions. Today our knowledge of food and what it does for our bodies is far more advanced than that of the ancient. Now we know about vitamins and how each kind of vitamin helps in the growth of a particular part of our bodies. There are on the market all kinds of vitamin pills which one can take to make up for one’s lack of certain important things which are needed for normal health. Of course, if we eat well and properly, the food that we eat will take care of our bodies without these pills and so there is no need to take any kinds of vitamin pills unless our doctor tells us that our bodies are short of something which can be supplied by them. Generally speaking, everything we eat does some good to our bodies, but if we eat too much of one kind of food and pay no attention to others, we may have too much of one kind of chemical substance and not enough of others. Then, we may be in trouble. We are often told that we must eat some meat at each meal in order to get the necessary protein. That is only partly true, for proteins are not found only in meat. We can also get them from some vegetables. The best advice about what to eat is that we should eat all kinds of food but never too much of any. 44 To get proteins, we must eat ____________.