Final answer:
The country song that featured trumpets, saxes, and trombones is 'New San Antonio Rose' by Bob Wills and His Texas Playboys, a classic example of Western Swing.
Step-by-step explanation:
The country song that featured trumpets, saxes, and trombones is New San Antonio Rose. This song, performed by Bob Wills and His Texas Playboys, marked a significant shift in the country music genre by introducing a full horn section. This style is often referred to as Western Swing, which blends elements of traditional country with swing and jazz influences. 'New San Antonio Rose' became a massive hit and is considered a classic example of this genre.