In the late 1800's, what helped flamenco grow and mature as a style?
Guitar music was added to the singing and dancing.
The Moors left Spain.
Special flamenco cafés were opened.
O Toca de palmas became a part of flamenco.

Special flamenco cafés were opened.

Explanation:

The Flamenco began matureness thanks to the opening of different cafes in Southern Spain in the mid-19th century. According to Spanish cantaor Fernando de Triana, the first special cafe was opened in 1842 in the city of Sevilla.

the urdan working class