Answer:
C. the false exteriors of African Americans
Explanation:
From the poem, we can discover that the "mask" is metaphoric. It tells that the mask is the false exteriors of African Americans.
From the poem, below is an excerpt:
"We wear the mask that grins and lies,
It hides our cheeks and shades our eyes,—"
The poet states "the mask that grins and lies" which simply points out that the mask sends out something false. It lies!
Option C is the correct answer.