49 Which of the following is the tone of the passage?
(A) pleading
(B) sarcastic
(C) conclusive
(D) alarming

Those who doubt the power of human beings to change Earth’s climate should look to the Arctic北極, and  shiver（因寒冷、疾病或恐懼而）輕微顫抖.  

There is no need to pore over仔細閱讀，研讀（pore翻譯：毛孔；氣孔；小孔）records of temperatures and atmospheric大氣 carbon-dioxide concentrations專心, 數量, 集中；聚集、濃度.

The process is starkly顯而易見 visible可見 in the shrinkage變狹; 減少 of the ice that covers the Arctic ocean.

In the past 30 years, the minimum coverage新聞報道、處理、包括 of summer ice has fallen by half; its volume容積；體積 has fallen by three-quarters.

On current trends, the Arctic ocean will be largely ice-free in summer by 2040. Climate-change sceptics懷疑態度 will shrug（表示不知道或不感興趣）聳（肩）.

Some may even celebrate: an ice-free Arctic ocean promises承諾 a shortcut近路，捷徑 for shipping船舶, 運輸 between the Pacific太平洋 coast of Asia and the Atlantic大西洋 coasts of Europe and the Americas, and the possibility of prospecting勘探 for perhaps a fifth of the planet’s undiscovered supplies of oil and natural gas.

Such reactions are profoundly深刻 misguided被誤導. Never mind that the low price of oil and gas means searching for them in the Arctic is no longer worthwhile值得.

Or that the much- vaunted被吹噓；誇耀 sea passages are likely to carry only a trickle液體, 少量 of trade.

The right response is fear. The Arctic is not merely（用於強調所說的即為所想表達的）僅僅 a bellwether前導 of matters climatic, but an actor in them.

The current period of global warming that Earth is undergoing經歷 is caused by certain gases in the atmosphere, notably特別地, 明顯 carbon dioxide.

These admit heat, in the form of sunlight, but block its radiation back into space, in the form of longer-wave-length infrared紅外線的.  

That traps防止逃走的物件, 陷阱 heat in the air, the water and the land. More carbon dioxide equals more warming a simple equation方程式；等式.  

Except it is not simple. A number of feedback loops complicate matters.

Some dampen潮濕 arming down; some speed it up. Two in the Arctic may speed it up quite a lot.

One is that seawater is much darker than ice. It absorbs heat rather than reflecting it back into space.

That melts more ice, which leaves more seawater exposed, which melts more ice. And so on等等. 

This helps explain why the Arctic is warming faster than the rest of the planet.

The deal on climate change made in Paris in 2015 is meant to stop Earth’s surface temperature rising by more than 2°C above pre-industrial工業 levels.

In the unlikely event that it is fully implemented實施，貫徹, 工具 winter temperatures over the Arctic ocean will still warm by between 5°C and 9°C compared with their 1986-2005 average.

The second feedback loop concerns not the water but the land.

In the Arctic much of this is permafrost永凍層.  

That frozen soil locks up a lot of organic material.

If the permafrost永凍層 melts its organic contents滿足的、主題、內容 can escape as a result of fire or decay腐蝕、衰敗, in the form of carbon dioxide or  methane甲烷 (which is a more potent強有力 greenhouse gas than CO2).

This will speed up global warming directly--and the soot煤灰 from the fires, when it settles on the ice, will darken it and thus speed its melting still more.

Which of the following is the tone of the passage? 
(A) plead翻譯：請求, 乞求，懇求, 陳述, （尤指在法庭上）為…辯護；申辯；認（罪）, 以…為解釋或藉口。
(B) sarcastic翻譯：諷刺的，嘲笑的，挖苦的。
(C) conclusive翻譯：無可置疑的；確實的；決定性的；結論性的。
(D) alarming翻譯：使人驚恐的，引起恐慌的；令人擔憂的。

(A) pleading 

訴願的；懇求的

(B) sarcastic 

諷刺的，嘲笑的，挖苦的；好挖苦人的，尖刻的

(C) conclusive

決定性的；確實的；最終的
(D) alarming 

驚人的；令人擔憂的；告急的

(A) pleading 懇求/辯論
(B) sarcastic 譏諷/諷刺/挖苦
(C) conclusive 決定性/令人信服/消除懷疑
(D) alarming 驚恐/警報/鬧鈴/動員令