2019 北京 第 44 题 单选题 区分题 2019_北京卷 (英语) 45. What is the main purpose of the passage? A. To assess the consequences of ocean colour changes.B. To analyse the composition of the ocean food chain.C. To explain the effects of climate change on oceans.D. To introduce a new method to study phytoplankton. 参考答案C ☆ 收藏不会，直接看解析查看原卷 →