The research findings, ___ were published in Nature, challenged traditional theories.

A. that

B. which

C. where

D. when

核心考点：非限制性定语从句解题思路：逗号后需用which引导非限制性定语从句选项分析：B正确（which指代前面整个主句）；A不能用于非限制性从句；C/D关系副词不符合语境易错点：可能误选that忽略逗号用法正确答案依据：唯一符合非限制性定语从句要求的选项

正确答案：B