Final answer:
The unique thing about the Beatles' signing with Parlophone records in terms of their music career was that they had full creative control over their music.
Step-by-step explanation:
The unique thing about the Beatles' signing with Parlophone records in terms of their music career was that they had full creative control over their music. This meant that they had the freedom to write and produce their own songs without interference from the record label.
The Beatles' creative control allowed them to experiment and push boundaries in their music, which contributed to their innovative and groundbreaking sound.