A dictionary is a type of a general information source that contains a compilation of alphabetically arranged words, their pronunciation, the part of speech the certain words belong and the usage of such words. The dictionary is part of the tertiary type of information sources because it no longer comes first hand from the original source and had already undergone several reviews and revisions before releasing the final dictionary for publication and circulation in the market.
I'm not 1000% confident in this answer but I believe it's B) to inform readers about the tactics Sparta and Rome used to hold cities and their effectiveness
