Final answer:
George Sand significantly influenced the career of composer Frédéric Chopin, providing support and an environment that contributed to the creation of some of his greatest works.
Step-by-step explanation:
Novelist George Sand, the pseudonym of Amantine-Lucile-Aurore Dupin, played a pivotal role in the career of composer Frédéric Chopin. The two shared a romantic and professional relationship, and during their affair, Sand was a strong influence on Chopin's life and work. Her support and the environment she provided at her estate in Nohant were conducive to Chopin's composition, and he created some of his most important works during this period. However, their relationship was also complex and had both positive and negative impacts on Chopin's career and health.