The Accompanying Table Shows Laura's Preference Ranking for Different Brands

The accompanying table shows Laura's preference ranking for different brands of jeans for 2011 and 2012. Her preferences are ranked from 1 to 4, where 4 is her most-preferred brand and 1 is her least-preferred brand. In 2011, 1,439 of the 28,000 females attending Laura's college owned a pair of Joe's Jeans. In 2012, a survey showed that 9,421 of the 28,560 females attending Laura's college owned a pair of Joe's Jeans. Based on this information, the change in Laura's preference ranking for Joe's Jeans from 2011 to 2012 can be best explained by the: $\begin{array}{lll}\text { brands of jeans }&2011 \text { Preference Ranking }&2012 \text { Preference Ranking }\\\text { Citizens of Humanity } & 2 & 2 \\\text { Apple Bottoms } & 1 & 1 \\\text { Seven for All Mankind } & 4 & 3 \\\text { joe's jeans } & 3 & 4\end{array}$

A) jean stitching effect.
B) fashion inferiority complex effect.
C) oligopolistic pricing effect.
D) bandwagon effect.
E) sociological advocacy effect.