How is an opera seria typically structured?

An opera seria is characterized by its structured use of alternating recitatives and arias, which serve distinct purposes within the narrative. Recitatives are primarily used to advance the plot and convey dialogue, allowing for a more conversational quality and moving the story along. In contrast, arias provide moments of emotional expression where characters can reflect on their feelings, often showcasing the singer's vocal technique and artistry.

This interplay between recitatives and arias is essential to the operatic form, as it allows for a dynamic musical experience that blends storytelling with emotional depth. The formal structure established in opera seria is rigorous and often involves elaborate baroque musical styles, making the alternation of these elements crucial to its identity.

In this context, the other choices do not align with the traditional structure of opera seria; for instance, improvisation goes against the highly composed nature of the genre, and focusing solely on spoken word neglects the musical aspects that define opera. Similarly, while monologues and dialogues may be present, they do not specifically capture the unique alternating format that is central to the opera seria style.