Which section involves altering thematic material from the exposition through mood, key, and modulations?

• A. Exposition
• B. Recapitulation
• C. Coda
• D. Development

Answer: (D)

In sonata-form music, the development is where the composer takes the ideas from the exposition and reworks them in new ways. Thematic material is fragmented, inverted, sequenced, and varied, and the harmony moves through a range of keys, often distant from the home key. Mood and character can shift dramatically as the material modulates and is transformed, building tension before the music heads toward a return of the themes in the recapitulation. This tonal exploration is what sets the development apart from the exposition (where ideas are introduced in the home key) and the recapitulation (where those ideas return in the home key), and from the coda (which serves to conclude).