The fourth alternative is correct (D).
Biography is a way of telling the story of a person's life in a book. This story can be told by the person himself, an autobiography, or by a third person, who can be a journalist, historian, friend or anyone who has knowledge about the person's life.
To have a real picture about a person's life, you should read their biographies, as many as possible. You can read the autobiography to understand the story told by the person himself, but you can also read the story told by a third person. This will give you more complete knowledge.