This assignment asks you to:
“…find two or three interesting subjects …that are similar enough to be comparable but different enough to be illuminating. “
You will find that focusing closely on a single thing, such as a particular person or specific event, will make research much easier.
Once you have two or three items to compare and an idea of how to compare them, start researching and see where the literature takes you. You may find that you need to change how you compare them or what you focus on.