This question is wrong, because there are in fact four abstract nouns in this sentence, two of which can be found among your options. An abstract noun is something that you cannot touch, because it doesn't have a form - those are words such as love, hatred, happiness, etc. So, here, among these examples, abstract nouns are both A. justice, and D. pursuit. However, if you only have to choose one, I'd go with A. justice, because I believe that is what your teacher wants you to pick. B. is a verb, and C. is a proper noun, not an abstract one.