①Most people know about endangered plants and animals. However, not everyone knows that many languages are in danger, too. Recently, there are almost 500 languages that are officially endangered. According to a study, 95% of the world's population only speak 6% of the existing 7,000 languages. This means that only 6% speak all the other languages. Some languages have fewer than a dozen speakers. There are several reasons why languages die out.
②A key reason is the influence of the dominant (主导的) languages. Generally, these languages are connected with social background and education. People who move to cities are forced to learn them. In most cases, the children do not learn their native language. In addition, many communities far away from towns and cities give up their languages in order to become an accepted part of the main culture. For example, India has lost 220 of 780 languages in the last 50 years. Once Hindi was regarded as the official language of India, the number of Hindi speakers increased from 260 million to over 420 million.
③Another reason is that the people who speak an endangered language may be in physical danger, such as from war or mas killing. Many languages of the native people in the Americas are either lost or endangered for this very reason. Natural disasters and disease can also wipe out all populations. When the village of Papua New Guinea was hit by an earthquake, all the people in it died. The language they spoke, Malol, also disappeared with them.
④Languages are part of cultures and show differences. Losing a language means losing a way to pass on culture. The whole world suffers because of the disappearance of cultural and language diversity (多样性). Therefore, efforts need to be made to protect endangered languages before they disappear forever.
B . 
C . 
D . 
