This excerpt features which sections of sonata form?

The answer centers on the structure of sonata form, which traditionally consists of three main sections: exposition, development, and recapitulation, often followed by a coda. In this context, the excerpt referenced is likely highlighting the development section, which is characterized by the exploration and transformation of themes introduced earlier in the exposition.

During the development, themes are varied, fragmented, and manipulated, creating tension and complexity before leading into the recapitulation, where the main themes return, typically restated in the original key. This process enhances the listener's emotional experience and creates a sense of resolution as the music moves toward the final sections.

Considering the other choices, the exposition usually precedes this, and options discussing coda or introduction do not align with the emphasis on development. Hence, identifying the focus on the development leading to the recapitulation captures the essence of that part of sonata form accurately.