I'd say C because the author includes a lot of statistics. For example, in paragraph 2, the author includes the statistic of 6.9% of all applicants getting accepted into Harvard.
The method the author use to convince the reader of her point of view is by citing the statistics of the previous admission record which shows the percentage rate in which college institutions accept new applicants. The statistics shows how top colleges and even public colleges are adopting a more stricter admission standards in accepting new applicants, which shows how competitive it is for new applicants to get accepted by the colleges.
