21.Clifford Brown is a partner in a money management firm. Brown recently attended a seminar where he learned about a quantitative model presented by Art Dixon. Upon returning to his office, Brown began testing the model and making a few minor alterations to it. He showed his model to his partners, who were impressed and decided to promote the model as proof of the money management firm's continuing innovation and value added. In the next newsletter mailed by the firm, Brown included a discussion of the model, the results of tests of the model, and financial data on several stocks selected by the model. These factual corporate financial data were taken from a Standard & Poor's publication. According to the CFA INSTITUTE Standards of Professional Conduct, which of the following actions is Brown required to take?

a.Brown must credit Dixon for having developed the original model, but he need not credit Standard & Poor's as the source of the data.

b.Brown need not credit either Dixon for having developed the original model or Standard & Poor's as the source of the data.

c.Brown must credit both Dixon for having developed the original model and Standard & Poor's as the source of the data.

d.Brown must credit Standard & Poor's as the source of the data, but he need not credit Dixon for having developed the original model.