The correct answer is a recent book about the Civil War.
A primary source indicates that the person who created the document witnessed the event first hand. This is why diaries, artifacts, and eyewitness accounts are all examples of primary sources.
A secondary source is one in which an individual writes about an event or topic without actually being there for the topic they are writing about. In this case, a recent book about the Civil War would be a secondary source since the writer was not at the actual war.
