Explanation:
The shapes that I see are a circle and two squares
Well, it seems like a multiple choice question; but you didn't provide any answers so I took the liberty of searching it up for you. The answer is O'Keeffe.
In my opinion, the answer is <span>B. the public concert system. Before that, performances were sponsored and held mainly in the rich patrons' mansions. Composers and performers earned their living thanks to their support. However, by the beginning of the 19th century, the era of commercial public concerts began. Composers could conduct their symphonies and other works in front of thousands of people (middle classes among them), in large concert halls. Even soloists held concerts (Franz Liszt being among the most notable and popular ones). The great concert piano appeared, such as we know today. </span>
