第二部分 阅读理解 （共两节，满分40分）
阅读下列短文，从每题所给的四个选项（A 、B 、C 和 D ）中，选出最佳选项，并在答题卡上将该项涂黑。
Is there a link between humans and climate change or not This question was first studied in the early 1900s. Since then, many scientists have thought that our actions do make a difference. In 1997, the Kyoto Protocol explained our role in the Earth’s changing atmosphere and set international limits for gas emissions(排放) from 2008 to 2012. Some countries have decided to continue these reductions until 2020. More recently, the Paris Agreement also aims to limit global warming. But just now how much warmer it will get depends on how deeply countries cut carbon emissions.
This is how much temperatures would rise by 2100 even if nations live up to the original Paris promises to reduce carbon emissions； this rise could still put coastal cities under water and drive over half of all species to extinction.
To meet this minimum goal, the Agreement requires countries to tighten(紧缩) emissions aims every five years. Even this increase could sink some islands, worse drought and drive a decrease of a third in the number of species.
This is the most challenging goal for temperature rise set by the Paris Agreement, after a push by