Read the following passage and mark the letter A, B, c or D on your answer sheet to indicate the correct answer to each of the questions

V.Read the following passage and mark the letter A, B, c or D on your answer sheet to indicate the correct answer to each of the questions.

Not so many years ago, the word vitamin was known only to a few scientists. Today it is very widely used, and the importance of vitamins in our foods is common knowledge.

Vitamins are life - giving substances found in foods and are needed for the proper growth and general health of the body. The different kinds of vitamins are indicated by letters of the alphabet. At the present time, vitamins A, Bl, B2, c, D, E and G are known. A proper diet should contain a collection of foods in which all of these vitamins are present. Vitamins are also prepared and sold in tablet and capsule form.

Each vitamin has its particular work to do in the life - giving process. Vitamin B1, for example, benefits appetite and digestion. It also helps the body grow. Another vitamin helps the blood to clot, so that danger of bleeding to death in case of injury is lessened. Still another makes the eyes stronger of seeing at night. Airplane pilots need plenty of this vitamin. Scientists think vitamins may have some effect on keeping the hair from turning gray.

29.What is the main idea of this passage?

A. diet in relation to health                   B. what vitamins are and what they do

C. prevention of diseases            D. how scientists discovered vitamins

30. We know the name of vitamins through______.

A. the pictures                                       B. the food

C. the different tastes                  D.the letters of the alphabet

31, The word “another” in the last paragraph refers to which of the following?

A. vitamin            B. food                     C. diet                     D. medicine

32.Which of the following is NOT true according to the passage?

A.    Vitamins can be taken only by eating the foods in which they are found.

B.    Vitamins can be prepared in tablet and capsule form.

C. Vitamins have an important effect on health.

D. Each vitamin has its particular work to do.

GIẢI THÍCH