Answer:
Primary sources typically originate directly from the event, people who took part in the event, an observer who is witnessing the event, or written thereby shortly after the event.
D. A journal excerpt from a person involved in the event in question
In the answer choice of D, it states that 1) The Journal is by a person involved in the event. This is the indication of the person directly participating in the event, thereby making it a primary source.
However, note that just because it is a primary source, does not mean it is the most accurate. Primary sources are heavily influenced by the person's beliefs as well as their perspective, and should not be used as the only basis for conclusion.