How Had Calvin Coolidge Won His Place on the 1920

How had Calvin Coolidge won his place on the 1920 Republican ticket?

A) He had gained a reputation as a passionate and engaging orator.
B) As governor, he had broken the strike of the Boston police force in 1919.
C) He had led American hunger relief efforts in Belgium during World War I.
D) He was the only Jewish American to have earned a medal of honor in the war.