2级
单选题Which of the following statements is true?
参考答案：B进入在线模考
B[分析]推断题型
见第五段：To understand the killer algae further，scientists must fully characterize their toxin and determine what stimulates them to attack．They also need to know if the algae are hurting fish populations。and whether pollutants make them move likely to attack．见下划线部分，因此可知还有更多的研究要做，因此B为答案。
见第五段：To understand the killer algae further，scientists must fully characterize their toxin and determine what stimulates them to attack．They also need to know if the algae are hurting fish populations。and whether pollutants make them move likely to attack．见下划线部分，因此可知还有更多的研究要做，因此B为答案。
