参考答案

正确答案：be brought under control by effort on a global basis
be brought under control by effort on a global basis 解析：题干中but后面分句中的it指的是pollution，“加以控制”是指it“被控制”，故用被动语态be brought under control表达。“通过全球的努力”可翻译为by effort on a global basis表达。