The right answer is the A: Symbolic and industrial.
Song of the Towers is one in the series of mural paintings Aspects of Negro Life (1934), created by African American artist Aaron Douglas (1900-1979), a great figure of the Harlem Renaissance. The murals trace the history of African Americans, up to their migration from the South to the North of the United States.
The mural is complex both in its formal aspects and in its meaning. A series of concentric circles and protruding and monumental prisms occupy the center of the composition, providing a lively and monumental frame to a jazz musician who is actively playing his saxophone. The Statue of Liberty is behind him, in the background. Although these symbolic elements seem to celebrate and relate African American heritage and culture and national identity, the images of two smoking factories and part of what it looks like a massive piece of industrial equipment, together with those of two exhausted African American workers, speak of the difficulties that African Americans encountered in those cities that promised progress and hope for the future.