What characterizes sonata-allegro form?

The sonata-allegro form is characterized by its structure, which includes two themes and three main sections: exposition, development, and recapitulation.

In the exposition, the main ideas or themes are introduced—often contrasting in character or key. The development section takes these themes and manipulates them through variation, exploration of different keys, and contrasting musical ideas, creating tension and complexity. Finally, the recapitulation revisits the themes from the exposition, typically in the original key, bringing a sense of resolution and closure to the movement.

This structural outline is fundamental to sonata-allegro form, particularly in the context of classical music, where composers like Haydn, Mozart, and Beethoven extensively employed this form for their symphonies, sonatas, and chamber works. Understanding this format aids greatly in analyzing and appreciating the development of Western classical music.

Other choices do not accurately describe the nuances of sonata-allegro form, lacking the essential elements needed to represent it fully.