In this task, you're given an article and an answer. Your task is to generate the fill-in-the-blank question for this answer based on the given article. The blanks are always at the end of the question, and can be filled with more than one word or phrase.

Article: Back in old times, people had little knowledge about the universe and nature. Things we now consider to be common sense were mysteries to our ancestors. Over the years, major breakthroughs have been made in science and many phenomena have been explained. But still, there are always questions we can't yet answer, and The Guardian has listed some of them. 1. What makes us human? Just looking at your DNA won't tell you - human DNA is 99 percent _ to that of the chimpanzee and, believe it or not, 50 percent identical to a banana's! A lot of the things we once thought were unique about us - language and tool use, recognizing ourselves in the mirror and so on - have since been seen in other animals. Perhaps it's our culture that makes the difference or maybe our ability to use fire. It's also possible that our capacity for co-operation and our trading skills are what make us unique. 2. Why do we dream? Given the fact that we spend around a third of our lives sleeping, shouldn't we know everything about it? Unfortunately, scientists are still searching for a complete explanation of what happens when we sleep and why we dream. Austrian psychologist Sigmund Freud believed dreams were the expressions of wishes that we can't fulfill in our real lives. Others have wondered whether dreams are just random "noise" coming from a sleeping brain. 3. Could we someday live forever? Apart from accidents, most people die because of diseases that can be treated and aging. And since many diseases, such as diabetes and cancer, are diseases of aging, treating aging itself could be the key to extending our lives. Our knowledge of what causes us to age - and what allows some animals to live longer than others - is expanding rapidly. And though we haven't quite worked out all the details, we've worked out some pieces of the puzzles such as DNA damage and metabolism , which are all leading to the invention of drugs that can slow down the aging process. If we're lucky enough to lengthen our lives, we might even get to see the day when all of these questions are answered.
Answer: to explain what were once mysteries to our ancestors
The main point of the passage is _ .

Article: In ancient Greek mythology we learn about a young man named Narcissus. He was so beautiful that he fell in love with his own reflection . He became obsessed , but soon realized that what he loved was not real. As a result, he became sad and died. In the place where he had stood appeared a soft yellow flower -a narcissus. This is where the word "narcissism" came from. Unfortunately, narcissism is often used to show disapproval because it is usually used to mean being self-centered and not caring about others. However, part of the reason that narcissism carries these negative meanings is that many people admire themselves in an unhealthy way. But the truth is that good self-love is necessary for our mental health, scientists say. A study published 10 years ago shows that low self-esteem is responsible for many social problems, and it can affect teenagers seriously. When they feel less confident and not as good as their classmates, teenagers are more likely to suffer from depression, commit suicide, get pregnant and bully others, according to the BBC. The other reason that narcissism is considered an ugly thing is because we are taught that we should care more about others than ourselves and that it's better to give than to receive. Thinking about others is the right thing to do, without question. But psychologists say that the love of others is actually based on self-love. If you see yourself as an unpleasant stranger, how can you be capable of making friends with anyone else? After all, you are closer to yourself than anyone else. After years of study, scientists also found that parents play a big part in building a child's self-belief. Only if the parents approve and accept their children, do they feel loved and learn to love themselves. The next time you look in the mirror, try to tell yourself that you are one of a kind. Pick out your best qualities and be proud of yourself.
Answer: can give teenagers mental health problems
According to the text, low self-esteem _ .

Article: Acting is such an over-crowded profession that the only advice that should be given to a young person thinking of going on the stage is "Don't!". But it is useless to try to discourage someone who feels that he must act, though the chances of his becoming famous are slim. The normal way to begin is to go to a drama school. Usually only students who show promise and talent are accepted, and the course lasts two years. Then the young actor or actress takes up work with a repertory company, usually as an assistant stage manager. This means doing everything that there is to do in the theatre: painting scenery, looking after the furniture, taking care of the costumes, and even acting in very small parts. It is very hard work indeed. The hours are long and the salary is tiny. But young actors with the stage in their blood are happy, waiting for the chances of working with a better company, or perhaps in films or television. Of course, some people have unusual chances which lead to fame and success without this long and dull training. Connie Pratt, for example, was just an ordinary girl working in a bicycle factory. A film producer happened to catch sight of her one morning waiting at a bus stop, as he drove past in his big car. He told the driver to stop, and he got out to speak to the girl. He asked her if she would like to go to the film studio to do a test, and at first she thought he was joking. Then she got angry and said she would call the police. It took the producer twenty minutes to tell Connie that he was serious. Then an appointment was made for her to go to the studio the next day. The test was successful. They gave her some necessary lessons and within a few weeks she was playing the leading part opposite one of the most famous actors of the day. Of Course, she was given a more dramatic name, which is now world-famous. But chances like this happen once in a blue moon!
Answer: there are already too many actors
According to the passage, the main reason why young people should be discouraged from becoming actors is _ .