求租英语完形填空正确答案

题目

求租英语完形填空正确答案
Scientists issued reports on the severe climate changes that could result __21__ the “greenhouse effect”—the gradual __22__ of the atmosphere caused by an increase in carbon dioxide __23__ from the burning of fossil fuels,saying that __24__ global temperatures could start to rise within a few decades and reach levels nine degrees Fahrenheit higher than today’s temperatures by the end of the next century.This,experts said,could create dangerous changes to global weather __25__.For instance,it could change annual amounts of rainfall,swell or dry up rivers,and __26__ the level of the seas.
While _27__ that this forecast was somewhat uncertain,scientists warned __28__ treating it as a cry of wolf.Although there is __29__ debate over how severe the greenhouse effect will be,one thing seems certain:Carbon dioxide levels are __30__ the rise.
21.A.about B.of C.in D.from
22.A.cooling B.warming C.hotting D.freezing
23.A.level B.degree C.extent D.range
24.A

答案

我自己答了啊
21 D
22 B
23 A
24 C
25 C
26 D
27 A
28 A
29 A
30 D