When a composer asks questions about what parts of a composition should be played by what instruments what is she considering

The composer is considering instrumentation, which refers to the choice and combination of instruments that will be used to perform a piece of music. This decision impacts the overall sound, texture, and mood of the composition. The composer must consider the range, timbre, and capabilities of each instrument when deciding which parts should be played by which instruments. They may also consider the balance and blend of the ensemble, and the desired stylistic or emotional effect.