Answer:
<u><em>She added these parts of Adolf Hitler and Anne Frank to show what else was going on in the world with Louie. It also showed what was going on at the time and how certain things affect the future of everyone</em></u>
Explanation:
answer is c . it is a relative clause describing the qualities of the brownies
D. friendly and respectful because it is a friendly letter, you don't want to be sarcastic which could come off as rude, and you don't want it to be formal either