A primary source is an artifact, a document, diary, manuscript, autobiography, a recording, or any other source of information that was created at the time under study. Therefore a soldier’s diary would be the correct answer as it was written either during or immediately after, while all the others are far from it. They would be considered secondary sources.
Macbeth drugged the guards with wine, which led to her stabbing Duncan. Afterwards she decides to frame the guards.
hope this helps
