다음 글의 밑줄 친 부분 중 어법상 옳지 않은 것은?Internatio… | [기상직 9급 영어] 17년 1회차 기출문제 상세 페이지

다음 글의 밑줄 친 부분 중 어법상 옳지 않은 것은?
Internationally, fuel ① used for aviation is tax exempt, and according to John Crayston from the Secretariat of the International Civil Aviation Organization (ICAO), "While the ICAO has established emissions standards for certain emissions there are no standards for CO2." The International Air Transport Association (IATA) estimates that aviation's share in climate change is at about 3.5 percent of the total contributions, ② which are predicted to climb to five percent by 2050. According to the Intergovernmental Panel on Climate Change (IPCC), aerosol particles that are emitted in aviation such as soot, metals and sulfuric acid can indirectly influence climate change ③ by causing additional cirrus clouds to form, which in turn trap the heat rising from the Earth's surface. The IPCC projects an overall global temperature increase from 34.7 to 40.1 degrees Fahrenheit between 1990 and 2100. Friends of the Earth London recommends that European travelers ④ opt for high-speed rail instead of flying, especially when going a relatively short distance.

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