Answer:
b. A brief funny or engaging tale about an actual person or incident.
Explanation:
An anecdote is a brief, funny story from a person's real experience. An anecdote is used to talk or refer to a particular event in a person's past to recount an amusing story to appeal emotionally to others.
In the given passage from "Mohandas Gandhi: Truth in Action" by Vanessa Wright, the anecdote used refers to the event when Gandhi had stolen gold from his brother. He later realized that his father's act of forgiving him was an act of "the principle of Ahimsa —of nonviolence—in action."
Thus, the correct answer is option b.