Answer:
Hôtel Van Eetvelde is the C. Art Nouveau style.
Step-by-step explanation:
Art Nouveau, "new art" in French, is a style which came to life around 1880-1890 in Europe and the United States. It is characterized by wanting to create something new and different, making an emphasis on the beauty of things.
This is the era in which things were mass produced so Art Nouveau tries to synthesis all styles.
Victor Horta was an important European Art Nouveau architect and his hotel received the UNESCO World Heritage award in 2000.