Final answer:
John Adams composed 'On the Transmigration of Souls' to commemorate the victims of the September 11 attacks, which premiered in 2002 and featured various spoken texts to honor the memories of those lost.
Step-by-step explanation:
The work by John Adams that was composed to commemorate the victims of the September 11, 2001, attacks is On the Transmigration of Souls. This orchestral piece premiered in 2002 and was crafted to evoke the emotions and reflective nature of the tragic events. Through spoken texts including names of the victims, fragments of messages left by those trapped in the buildings, and the words of missing-persons posters, Adams created a soundscape seeking to capture an aura of remembrance and tribute.
The piece incorporates recorded sounds from the day of the attacks, including voicemails, sounds of sirens, and names of the victims.