Final answer:
From the provided historical context, the characteristic of "my song" in the poem is (C) a song of protest and defiance, as seen in the themes of struggle and resistance to racial inequality in the works of Hughes and McKay.
Step-by-step explanation:
The "song" referenced throughout the poem embodies a more abstract set of themes and ideas rather than being a literal song. Given the historical context and the poetry excerpts provided, the most fitting characteristic is (C) It is a song of protest and defiance. This is evident in the themes explored by poets such as Langston Hughes and Claude McKay, where the struggle against racial inequality and resistance is stark. Hughes' poetry, like "I, Too, Sing America," encapsulates the resolve to overcome disparagement and grow stronger in the face of segregation. Similarly, McKay's "If We Must Die" counsels a defiant stance against racist violence. Both these works illustrate how the term "song" can be metaphorical, representing a collective voice of challenge and resilience amid racial and social adversity.