B, handwritten letters, because the letters are probably the most credible, especially since they're a first-hand account of things that happened to your ancestors, and as WorldlyGlass45 mentioned in their answer to this question on another post, you'll most likely get the most info from the letters as well.
Questions that don’t lead to a yes/no answer. ex Why do you think that is the best approach? How would you apply that idea
What do you need help with
Writing a paper:
Writing a paper can be challenging, however, if it is approached step by step it isn't as scary as it seems. First, obtain a lot of information that are credible about your topic. Then organize your thoughts by making an organization map. Thirdly, begin writing your intro and come up with a thesis statement, which is usually the last sentence of the intro. Finally start writing your paper based upon your thesis statement in which you should have several ideas written down.
Hopefully this helps.