Which statement about Paul Whiteman's life and career is not true?

The statement that Paul Whiteman made a conscientious endeavor to hire musicians of color in his orchestra is not true because, while he was a significant figure in the early 20th-century music scene and did try to elevate jazz through orchestral interpretation, his hiring practices predominantly reflected the racial attitudes of his time. Whiteman's orchestras were mostly comprised of white musicians, and there were limited opportunities for musicians of color in his ensembles.

In contrast, the other statements accurately reflect aspects of his career and impact on music. Whiteman's "Ambassador Orchestra" was indeed extremely popular and known for its record sales, bringing jazz and orchestral music to a broader audience during the 1920s. Balancing improvisation with careful arrangement was a hallmark of his style, as he sought to blend classical music elements with jazz, making it more palatable for mainstream audiences. While some authorities criticized him for his approach to jazz, suggesting that he diluted its authenticity, he was also noted for striving to bridge racial divides in music, even if he did not fully succeed in diversifying his orchestra.