Premise: Survey identified a group of secretaries with very positive attitudes. They responded "Strongly Agree" to statements regarding their work ( i.e. liking word processing & learning new secretary skills). They've also been rated as excellent workers by their supervisors (contrary to secretaries with less positive attitudes).

Conclusion: Clearly, these secretaries' positive attitudes toward their work produced excellent job performance.

B.) This confuses the author's conclusion with circular reasoning. The author never stated that the secretaries' attitudes produced their performance in the premises. That was original IP that came from the conclusion.

E.) We don't know that their positive attitudes caused or "produced" their excellent job performance.