Read the article and select the best answer. Article: Scientists have long had it in their mind to make a robot lizard . They began with finding out why a lizard can hang on a wall. They noticed the lizard's toes were unique: They have suckers , which enable it to hang on walls. They, therefore, made a robot with suckers on its hands and feet. The robot could hang on the wall but fell off when crawling. So, they went on researching. 6 years ago, scientists discovered that suckers only were not enough. It is the bristles on each foot that adds friction and static adsorption that makes a lizard move on the smooth wall easily without falling down. Then scientists made great efforts to fix thick bristles to the robot's hands and feet. However, the effect was not satisfactory. The robot still couldn't attach itself firmly to the wall. Scientists got puzzled: How on earth can the lizard crawl on an extremely smooth wall or even on a ceiling without dropping off? An accidental finding inspired them: One day a scientist happened to see an animal attack a lizard and bite off its tail. The lizard broke away from the animal's teeth and threw itself on a wall to escape, only to fall off heavily on the ground. The scientist wondered: Is it the tail that plays an important role in its travelling on the wall? He caught some lizards for an experiment. The result proved his assumption: A tailless lizard has no trouble walking on an ordinary wall but can't on a smooth one. A further study showed the lizard's tail can prevent it falling over backward and, what's more, that the tail acts as an additional leg while one of the lizard's legs leaves the wall, which is always the case while it is walking on the wall. Thus, Tailbot, a super tailed robot, is born. Question: The biggest importance of a lizard's tail lies in _ . Options: A: helping support the body B: serving as another leg C: sticking to the wall D: stopping slipping
B

Read the article and select the best answer. Article: Expressing emotions is important rather than hiding them or keeping them inside. Everyone feels negative emotions such as anger and needs to deal with them. But there are healthy ways to express anger and ways to control it. Shouting bad words at someone will hurt the other person or make them angry too. If you feel angry, it is best to think before you speak. Some people in the UK use the expression "take a deep breath and count to 10", meaning take a pause, breathe deeply and let yourself calm down instead of getting angry. Another expression people use to say they are controlling their anger is "biting their lip". This means not letting the bad words come out of their mouth. If you cannot think of anything but bad words, it is probably best to "bite your lip." But sometimes letting all your anger out can be cathartic , as long as you do it at the right place and time. If you have just had a bad day, you could go into a room by yourself and scream or yell very loudly. Or if you want to hit someone or smash something, you could hit a pillow instead. Then after you let your frustration out this way, you'll be able to deal with your problems more calmly. If you do lose your temper with someone and swear at them, though, you need to apologize. One way to do this is to say "pardon my French". This expression has been used for many years as an apology for bad language. Then you can calmly explain what made you upset. Question: What does letting out your frustration help you to do? Options: A: Make others more upset. B: Feel happier about yourself . C: Solve a problem calmly. D: It is no help at all.
C

*Question*
Read the article and select the best answer. Article: Kayaking is an activity enjoyed by many people of all ages. It requires little or no experience and nearly anyone of any skill level can participate. It's most popular as a summertime sport, but it is also a great activity during the winter. Kayaking also seems ly friendly to the environment; more so than speed boating or water skiing. Because a kayak doesn't create large or frequent waves, require fuel, or scatter hazards into the air, it is indeed a fairly safe activity for humans and wildlife alike. Kayaking on freshwater lakes and streams creates little turbulence and therefore does not disturb fish or other aquatic life. Actually, the gentle paddling and movement of the kayak helps to bring seaweed to the surface, making for convenient snacking to the fish. However, there is a drawback to the all-you-can-buffet for your fishy friends. In addition to bringing food to the surface, kayaking also stirs up litter that's been hiding beneath the waters. Some aquatic animals will mistake it for food. This could cause the animals to choke on the indigestible litter, leading to death. As hazardous as this sounds, it isn't very likely for such an event to take place. Most litter in lakes and streams is found along the shoreline and settles in the sand and dirt, and isn't likely to drift away to the main body of water. ^ . And because kayaks do not have a motor, fish have no risk of getting caught underneath the boat. One potential hazard that results from kayaking is human waste. This depends solely on where you plan to kayak, and if there are resources available (such as campsites) along the shoreline. When there are no facilities in sight, you're paddling in the middle of a lake, and nature calls, then often you are given no choice but to expel your waste in the middle of the water. While human waste is considered biodegradable, it can be harmful when swallowed by fish. The only preventative measure is to avoid using the water as a restroom. Some public lakes and streams have taken steps to preserve the... Question: Which word or expression is closest in meaning to "biodegradable"? Options: A: Recycled. B: Environmentally harmless. C: Poisonous. D: Sustainable.
**Answer**
B