阅读下面短文，从短文后所给各题的四个选项（A、B、C、D）中，选出可以填入空白处的最佳选项．
Many wild animals are facing the danger of extinction（灭绝）， because the environment that they are living in has
(1) greatly． For example， with the development of cities， the using of insecticide and serious pollution， their living areas have become
(2) ． Many of the wild animals are lack of food． People hunt wild animals in large areas． Tigers are hunted for fur or bones
(3) they can only live in the nature reserves
(4) living in the wild． Some grassland is destroyed so that the sandstorms come into being influencing distant cities，
(5) cities in northern China or north-western China．
Luckily， human beings have realized the
(6) of protecting wild animals and environment and have taken some practical actions． Don't
(7) trees， don't abuse agrochemical or insecticide． We should protect headwaters and air which help protect habitat（栖息地）． Some organizations raise money for animals and
(8) leaflets in the street to call on more people to focus on the environment and wild animals． The
(9) has made some laws to prevent people from hunting wild animals and shut down some factories which do harm to the environment． We believe the number of some endangered wild animals will
(10) in the near future． Animals are important to our life and we should protect them．