Critical Reasoning

Following several years of declining advertising sales, the Greenville Times re-organised its advertising sales force 2 years ago. Before the re-organisation, the sales force was organized geographically, with some sales representatives concentrating on city centre businesses and others concentrating on different outlying regions. The reorganisation attempted to increase the sales persons' knowledge of client businesses by having each sales representative deal with only one type of industry and retailing. After the re-organisation, sales increased.
In assessing whether the improvement in advertising sales can be properly attributed to re-organisation, it would be helpful to find out each of the following except:
A) 2 years ago what proportion of Greenville Time's revenue was generated by advertising sales
B) Has the circulation of Greenville Times increased substantially in the last 2 years
C) Has there been substantial turnover in the personnel in advertising over last 2 years
D) Before the reorganisation had sales representatives found it difficult to keep up with relevant developments in the businesses they were assigned to?
E) Has the economy in Greenville and surrounding regions been growing rapidly over last 2 years?