The popularity of sports in the 1920 rose mainly because of

 D) an increase in leisure time of most American workers.

Explanation: Changes in pay and working hours resulted in an increase in leisure time of most American workers. Many people turned to watching organized sports, both professional and collegiate, in their spare time.

it provided for selection of government employees through competitive examinations. it also made it unlawful to fire or demote covered employees for political reasons or to require them to give political service or payment, and it set up a civil service commission to enforce the law.

explanation: