Which of the following best describes the United States' approach to military aviation in the $1920$s$?$

The United States created a separate branch of the military $($the Air Force$)$ to handle the development and management of air power.

Both the Army and the Navy largely ignored aviation development.

While the Army developed aviation, the Navy, angered by Billy Mitchell, ceased all aviation development.

Both the Army and the Navy increased the number of aircraft and pilots in each service, but did not go so far as to create a separate Air Force.