<em>B. which of his or her friend should write a letter
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<u>Explanation:</u>
Friends or relatives do not write recommendation letters of the student. This is a professionaldocument that is supposed to be written by a professor of the student, who understands the capabilities of the students based on regular class assessments.
Failure to which, the recommendationletter can quickly be declined because of failure to meet the academic standards. Thus any form of an application letter should be at any time written by somebody considered professional in one’s area of study or application.