Answer:
B
Step-by-step explanation:
It's from the perspective of a former slave themselves. It's the first source you get your information. Like a friend saw something, and they're the first one to know about it. That's a primary source. Then they told a second friend, who knows about it from an accurate, up-close witness. The second friend is a secondary source. The second friend tells the third friend, hearing the story from the second friend's perspective, but it might not be as accurate as of the first friend's. The third friend is your tertiary source, and so on.
Please let me know if this helps with future problems!