Read the following article and select the best answer. Article: What's the strongest part of your body? Your head? Bones? It's your teeth. There is a special thing called enamel in teeth. It is the hardest thing in the human body and keeps bacteria away. However, teeth are hurt easily to problems and disease. September 20 is National Teeth-loving Day in China. Let's pay attention to the health of our teeth. Teeth problems are common around the world. Most children and young adults have tooth decay . A study which come out on China Health Monthly magazine this year showed that 40.74% of a sample of 1,306 Chinese students under age 15 has decayed teeth. Food that is rich in sugar increases the risk of tooth decay. After you eat, bacteria go crazy over the sugar on your teeth. The bacteria turn sugar into acids that eat away at tooth enamel. This causes holes in your teeth. Another common problem is crooked teeth . When your new teeth begin to grow and the old teeth haven't fallen out, there isn't enough space for the new ones. This causes crooked teeth. Don't worry. Here are some ways to keep your teeth healthy. *Brush at least twice a day in the morning and in the evening. *Learn to use dental floss . The floss gets rid of food that's hidden where your toothbrush can't get it. *Visit a dentist. He or she can check if you have any dental problems and help you clean your teeth. *Pay attention to what you eat. It's better to eat lots of fruit and vegetables instead of fries and drink water instead of soda. *Wear braces to make your teeth straight and beautiful. Question: What's the strongest part in the human body according to the passage? - Bones. - Teeth. - Head. - Bactria.
Teeth.