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 from 35 to 42.
The main cause of tooth decay is acid, which is produced by bacteria in the mouth. The acid removes minerals from tooth enamel, allowing tooth decay to begin; the saliva in your mouth encourages remineralization and neutralizes the acid. The rate at which bacteria in the mouth produce acid depends on the amount of plaque on the teeth, the composition of the microbial flora, and whether the bacteria of the plaque have been “primed” by frequent exposure to sugar. To keep your teeth healthy, a regular dental hygiene program should be followed.
Removing plaque with a toothbrush and dental floss temporarily reduces the numbers of bacteria in the mouth and thus reduces tooth decay. It also makes the surfaces of the teeth more accessible, enabling saliva to neutralize acid and remineralize lesions. If fluoride is present in drinking water when teeth are forming, some fluoride is incorporated into the enamel of the teeth, making them more resistant to attack by acid. Fluoride toothpaste seems to act in another way, by promoting the remineralization of early carious lesions.
In addition to a regular dental hygiene program, a good way to keep your teeth healthy is to reduce your intake of sweet food. The least cavity-causing way to eat sweets is to have them with meals and not between. The number of times you eat sweets rather than the total amount determines how much harmful acid the bacteria in your saliva produce. But the amount of sweets influences the quality of your saliva. Avoid, if you can, sticky sweets that stay in your mouth a long time. Also try to brush and floss your teeth after eating sugary foods. Even rinsing your mouth with water is effective. Whenever possible, eat foods with fiber, such as raw carrot sticks, apples, celery sticks, etc., that scrape off plaque, acting as a toothbrush. Cavities can be greatly reduced if these rules are followed when eating sweets.
What can be concluded from the passage about sweets?
A. All sweets should be avoided.
B. Sweets should be eaten with care.
C. It is better to eat sweets a little at a time throughout the day.
D. Sticky sweets are less harmful than other sweets.
Chọn đáp án B
Điều gì có thể được kết luận từ bài đọc về đồ ngọt?
A. Chúng ta nên tránh tất các loại đồ ngọt
B. Đồ ngọt phải được ăn cẩn thận
C. Tôt hơn nên ăn đồ ngọt riêng biệt trong ngày
D. Đồ ngọt dẻo thì ít có hại hon các loại đồ ngọt khác
Dẫn chứng: In addition to a regular dental hygiene program, a good way to keep your teeth healthy is to reduce your intake of sweet food. The least cavity-causing way to eat sweets is to have them with meals and not between. (Ngoài việc vệ sinh răng miệng thường xuyên thì cách tốt để giữ răng khoe là giảm lượng đồ ngọt. Cách ít gây sâu răng nhất khi ăn đồ ngọt là ăn cùng với các bữa ăn chứ không phải giữa các bữa ăn.) => Phải ăn đồ ngọt cẩn thận.