Answer:
C. Round and dynamic.
Explanation:
James Baldwin's "Sonny's Blues" revolves around the story of a young man named Sunny, though from the perspective of his elder brother, an unnamed narrator. This short story focuses on the themes of family, suffering, salvation, relief, control, help, etc.
In the short story, Sunny can be taken as a round and dynamic character. This is because he is an interesting character, deep and layered with numerous sides or aspects to his personality. He is constantly changing, making the story interesting and intriguing. He is also a dynamic character in that he changed at the end of the story.
Thus, the correct answer is option c.