What is the “mystery sound” on page 144?

Imagine if going to work every day meant your life thats the reality that meat packers in this county face with some of the highest rates of injury and death of any profession i myself worked at such a facility for two years and can resport on the unsafe conditions firsthand

May someone me answer these questions

What does it appear that the speaker of the poem wants to do? caged bird by alicia keys question options: sing be adored by fans be set free from public scrutiny be shared with the whole world