The rise of modernism and functionalism in architecture and design, which emphasized simplicity, practicality, and the rejection of ornamentation, led to the decline of Art Nouveau's popularity.

Henri Matisse is associated with the Fauvism movement, not Art Nouveau.

Art Nouveau architecture is characterized by the use of curved lines and organic forms, the incorporation of stained glass windows, and the use of natural materials such as wood and stone.

Paris, London, Vienna, and Barcelona were all major centers of Art Nouveau.

La Revue Blanche was an influential Art Nouveau magazine published in Paris.

René Lalique is known for his Art Nouveau jewelry designs.

Sagrada Família, Casa Batlló, and Park Güell are all Art Nouveau buildings designed by Antoni Gaudí in Barcelona.

Art Nouveau furniture is characterized by the use of curved lines and organic forms, the use of natural materials such as wood and leather, and the use of bright colors. Geometric patterns are not a characteristic of Art Nouveau furniture.

Jugendstil was the name of the Art Nouveau movement in Germany.

Art Nouveau posters are characterized by the use of flat colors, bold lines and curves, and asymmetry. Realistic imagery is not a characteristic of Art Nouveau posters.

Modernismo was the name of the Art Nouveau movement in Spain.

Paul Cézanne is associated with the Post-Impressionism movement, not Art Nouveau.

Liberty Style was the name of the Art Nouveau movement in Italy.

Art Nouveau jewelry is characterized by the use of natural motifs, bright colors, and precious metals and stones. Geometric patterns are not a characteristic of Art Nouveau jewelry.

Les XX was the name of the Art Nouveau movement in Belgium.