She decided to keep reticent about the unpleasant past and ______ it to memory.

【正确答案】 C

【答案解析】 动词同义辨析。attribute“认为……是，归因于……”；allude“提及，暗指”；commit“托付，交付”；credit“赊购，借款，赞扬”。故答案为C。