Q: Read the following article and select the best answer. Article: Nearly all of today's Native Americans in North, Central and South America can trace their ancestry to just six women whose descendants immigrated around 20,000 years ago, a DNA study suggests. The finding does not mean that only these six women gave rise to migrants who crossed into North America from Asia in the earliest population of the continent.Rather, it suggests that only six left a particular DNA legacy that persists to today in about 95% of Native Americans, said study co-author Ugo Perego in Utah. "The women did not necessarily arrive together, nor even all live at the same time," he said.Results indicate the women arrived sometime between 18,000 and 21,000 years ago. The work was published this week by the journal PLoS One.Perego is from the Sorenson Molecular Genealogy Foundation in Salt Lake City and the University of Pavia in Italy.The work confirms the previous indications of just six maternal lineages, as well as a date of around 20,000 years ago when the first people in North America arrived after crossing a land bridge from Asia, Perego said. The researchers studied mitochondrial DNA, which is passed only from mother to daughter.They created a "family tree" that traces the different DNA _ found in today's Native Americans.By noting mutations in each branch and applying a formula for how often such mutations arise, they calculated how old each branch was.That indicated when each branch arose in a single woman. The six "founding mothers" obviously did not live in Asia because the DNA signatures they left behind are not found there, Perego said.So they probably lived in Beringia, the now-submerged land bridge that stretched to North America, he said. Question: What didn't Ugo Perego and his team do? - They used a "family tree" to analyze the findings. - They focused on life styles of the original women. - They clarified genetic changes in the family tree. - They studied how long each branch had developed.
A: They focused on life styles of the original women.

Q: Read the following article and select the best answer. Article: People are different. Some are _ . These people are outgoing, confident, and know the "gift of the gab". They also feel very comfortable when in groups of people. Unfortunately we have the other extreme. This is the introvert. The introvert feels sick in crowds, and does not like them. These people feel awkward in the crowds, when placed in this type of situation. Many introverts are shy and lack confidence. They need to get used to people, and want to run away when questioned by people. The introvert feels very lonely in a crowd, but this could happen to the outgoing as well. I think that I fall into the middle of the two kinds. Sometimes if I am comfortable about the type of people in the crowds, I feel welcome. If for some reason the crowd consists of different types of people, then I do not feel very comfortable in the crowd. So what do I do when I suddenly feel lost and alone in the crowd? I try to calm my mind by taking deep breath and telling myself that even this will pass. I then try, and get away from the crowd by making excuses or even trying to get to my car and go home. This, of course, is a poor excuse and doesn't often work well. These are excuses that are employed. The ones that I am not so proud of are acting like I have an emergency to go to. This is a very good lie, but I feel really bad afterwards. I have tried this one, and have succeeded. I try and find someone who feels just like I do. I then try and make a new friend. Sometimes this works and sometimes it does not. This is quite a noble way of staying in the crowd. Question: The word "extrovert" is most likely to mean _ . - serious - excited - outgoing - nervous
A: outgoing

Q: Read the following article and select the best answer. Article: We've all heard about the power of positive thinking, but a recent study found that people who think they're getting fit actually get more positive benefits from activity, according to a Reuters Health article. The study examined hotel housekeepers over a period of four weeks. Some of the housekeepers were told that their work duties gave them enough activity to meet the Surgeon General's health guidelines . Another group of housekeepers were told nothing. After four weeks, the housekeepers who believed their work activity counted as exercise lost weight and body fat, and their blood pressure went down. The results of this study suggest that it's important to understand and believe in the positive benefits of your activity. So here are a few things to think about the next time you exercise: Just thirty minutes of quick walking each day can greatly reduce your risk of a heart attack. Even your housework -- like yard work and house cleaning -- can help you burn calories and increase your fitness levels. Weight bearing activity just a few times a week can build bone density and reduce your chances of developing osteoporosis . Three 10-minute workouts throughout the day are just as good to your health as one long workout. Moderate amounts of exercise have been linked to lower rates of heart disease, stroke and even cancer. Strength training can help make daily activities like carrying bags or laundry feel easier. Regular exercise will reduce stress, keep you in a good mood and improve the quality of your sleep. Question: The main purpose of this passage is to _ . - encourage people to think they will get fit in different activities - tell people how to finish the work duties better - tell people how to lose weight - advise people to do more housework
A: encourage people to think they will get fit in different activities

Q: Read the following article and select the best answer. Article: Almost every child is scared of something, from monsters in the cupboard to dogs in the park. But the fact that such fears are common and normal doesn't mean they can be taken lightly. Kids experience fears and phobias much more strongly than adults. And the influence of the fear can be physical as well as psychological . It can build up so they almost seem scared of everything--a kind of childhood anxiety. Dr. Creswell says: "Your child may always seem to expect the worst to happen and lack confidence in his or her ability to deal with any challenge." So don't make the same old mistake of treating them as if they're silly for being a"scaredy cat". Handling the fears is essential. Children can be born nervous and, if you have such a baby, you'll tend to prevent them from getting worried. So if they fear dogs, you'll keep them away from dogs, but in fact that can just confirm to the child that dogs are scary. What is worse, keeping your child away from what they fear can turn that feeling into a phobia. Instead, you should encourage them to get in touch with the thing they fear, in a safe and supportive environment. Dr. Andy Field, a researcher of childhood fears, says: "You shouldn't force, for example, a dog anxious child to go up to a dog. But you can approach it yourself, show them there is nothing to be afraid of, stroke( ) it, and talk about the dog being friendly. Once your child dares to stroke a dog-one that's good with children, of course---then you should encourage them to carry on until they feel calmer, and reward them for'being brave'." Question: If we fail to help children to overcome fears, they will _ . - make the same old mistake - overcome them by themselves - experience the worst of things - grow up lacking self-confidence
A: grow up lacking self-confidence