What does the term 'alla' mean in music?

The term 'alla' in music is derived from Italian and translates to "in the manner of." It is often used as part of other musical terms to indicate that a piece or a section should be played in a style or manner characteristic of a specific tradition or genre. For instance, you might encounter phrases like "alla marcia," meaning in the manner of a march, or "alla breve," which refers to a specific type of meter.

In this context, the other options do not accurately fit the definition of 'alla.' While "well marked," "with an added octave," and "slowly" may describe certain musical elements or techniques, they do not convey the essence of imitating or following the style as encapsulated in the term 'alla.' Therefore, understanding that 'alla' signifies a stylistic approach helps clarify its usage in different musical contexts.