题目

下列各句中，加点的成语使用恰当的一句是 A．司机张师傅冒着生命危险解救乘客的事迹，一经新闻媒体报道，就被传得满城风雨，感动了无数市民。 B．近年来，在种种灾害面前，各级政府防患未然，及时启动应急预案，力争把人民的生命财产损失降到最低限度。  C．这些“环保老人”利用晨练的机会，将游客丢弃在景点的垃圾信手拈来，集中带到山下，分类处理。  D．“生命的价值在于厚度而不在于长度，在于奉献而不在于获取……”院士的一番 Polar bears(北极熊) are in great danger. And human beings are possibly the cause of the danger. As we burn gas to produce electricity or get us around town in our cars and trucks, we create tons of carbon dioxide (二氧化碳). This is causing global warming. Polar bears need sea ice to live because the ice is their hunting ground. The bears’ main source of food is the meat of seals(海豹). These animals come to surface holes in the ice to breath. It is there that the polar bears catch the seals. Without any ice, there is nowhere for bears to hunt. The seals hardly come onto the land and spend their time out on the sea ice.In recent years, the seal ice has disappeared in the Arctic during the late summer. This is dangerous for the polar bears, as they depend almost only on seals for food. Unlike brown and black bears, polar bears do not hibernate(冬眠) during the winter. Only female polar bears will go into a “little house” and stay for a long time if they are giving birth to baby bears.It may be strange to think about, but winter is the time for polar bears to get food while summer is the time of hunger. The bears have got used to a cold world, and they need the low temperatures in order to stay alive. If the world continues to warm up and sea ice is absent for longer and longer periods of time, polar bears might unluckily go the way of dinosaurs (恐龙).【1】Because of human beings, all the bears in the world are facing great danger now.【2】If there are no seals on the sea ice, polar bears may have no food to eat.【3】Unlike brown and black bears, only female polar hibernate in winter.【4】Polar bears can get much more food in summer than in winter.【5】Global warming may make polar bears die out in the future.