According to the author, most students ( ).

参考解析：

根据文中第一段"The world's environment is surprisingly healthy. Discuss." If that were an examination topic, most students would tear it apart, offering a long list of complaints: …Yet the students who should be given the highest marks would actually be those who agreed with the statement. 可知，作者认为与大多数学生的做法以及对环境的看法相比，那些认同“当前全球环境前所未有的健康”这句话的学生应当得高分。选项A：相信全球环境和人们所认为的并不一样；选项B：认为全球现在处在不利的生态环境中；选项C：对全球环境的状况一点都不担心；选项D：对环境有更深层次的思考。结合第一段表达可知作者认为大多数学生都认为当前全球环境是非常糟糕的。故本题正确答案选B。