The third source I think.
Answer:
B. Booking Agents
Explanation:
Right for my Plato and Edmentum peeps
An orchestra is defined as a large instrumental ensemble typical of classical music. An orchestra features bass, brass, strings, woodwinds, and percussions. In the list given above, the section that is not one of the four groups in the orchestral palette is the voices. The answer would be "voices".
It is because flash mobs is a group of people dancing to music and music is art.
