答案：C

题目分析：考查固定词组，react to意思“对……做出反应”，句子意思“一个人怎样对批评做出反应意味着成功和失败的不同”，所以选C

点评：句子How a person reacts to criticism often means…是个从句，引导词是how，句子How a person reacts to criticism做整个句子的主语。