The correct answer is B) written or created by a person who experienced an event.
To be considered a primary source, a source must be written or created by a person who experienced an event.
When doing research, an author has to use primary and secondary resources to support its arguments. Primary sources are the ones written or created by a person who experienced an event. That is the main characteristic of primary sources. It could be a letter o a photograph of people that witnessed or participated in the event. Secondary resources could be books written by other researches or encyclopedias.