This question is about understanding the meaning of specific terms. The correct answer is 'B. referee,' which means to act as a judge or to review something, often an article, for its quality or authenticity. Option A, 'primacy,' means the state of being first or most important, which does not relate to the act of reviewing. Option C, 'definition,' is a statement of the meaning of a word or phrase, which is not an action. Option D, 'separate,' means to divide or keep apart, which is not related to the act of reviewing.