李明攀的回答：

个人认为是可以的 sources being the most accurate 这里应该是现在分词作后置定语，修饰前面的sources,相当于对应的定语从句，sources which are the most accurate be the most accurate 是最精确的，其现在分词形式是being the most accurate，作后置定语，就如 The man talking to her is Tom.= The man who is talking to her is Tom.

曹艳的回答：

个人认为是可以的 sources being the most accurate 这里应该是现在分词作后置定语，修饰前面的sources,相当于对应的定语从句，sources which are the most accurate be the most accurate 是最精确的，其现在分词形式是being the most accurate，作后置定语，就如 The man talking to her is Tom.= The man who is talking to her is Tom.

梦会醒的回答：

不能替换 1、这是一个独立主格结构的省略句，还原原句为 (The document) being the most accurate at the time of the document preparation, the document summarises data and information from these sources. 2、独立主格的结构形式为：n+分词（现代/过去分词）【当然还有其他形式】表示时间、条件等原因时，相当于一个状语从句。 3、由于前后主语一致，为避免重复，省略主语，突出想要说的重要信息，所以省略后变为 being the most accurate at the time of the document preparation，the document summarises data and information from these sources. 4、这句不可以替换为简单的which are定语从句，而且先行词也不是sources，而是The document。