A Clarity because clarity means the same as "how clearly". Or the measurement of "how clear something is", like the clarity of water. If you practiced new Vocab words with good clarity or with clarity, it means you understand them and can spell them well.
There isn't really a right answer to this, it's more opinion based. What did you cover in class? If its relating to foodborne illness and sanitation then you could say, "One fact that I thought was most important was to avoid cross contamination with certain foods like poultry or raw eggs"
