Cites sources and presents information in an unbiased manner.
presents factual information in a clear and accurate manner
Explanation:
If you must use a secondary source (as in, a source that is not directly connected to know), the least you can look for is a source that has a history of being unbiased, factual, transparent and accurate. In that way, at least, you can consider how trusted can the source be. When a source expresses strong opinion about something, most likely it's very biased and has a goal behind presenting information.
The holocaust were Jewish slaved taken by the Germans to be tested on or just plainly tortured, those actions eventually led up to the Geneva convention