The reason why Chopin's "Fantasie Impromptu," was almost lost without it being published was that A. Chopin made his sister promise to burn it after his death.
Frédéric Chopin was a leading musician in the 19th century when he lived in Paris and other parts of Europe.
Chopin was a child prodigy who became a great musical composer such that his style was used as inspiration by many other composers around the world.
Frédéric Chopin left behind a body of work known as the "Fantasie Impromptu" which he didn't publish and then made his sister promise not to publish it or any other unpublished work he had.
His wishes were turned down after he died and the "Fantasie Impromptu" was released to widespread acclaim.
In conclusion, option A is correct.
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