Fill in the blanks with the most appropriate words.
A preposition is a word which comes before a noun or a pronoun and establishes a relationship between the elements of a clause or words. Option C)with/ over is correct as with and over indicate relation and something that is connected with. The other options are wrong as at, about, on, and against indicate a specific location, a piece of information, and that someone is not in favour of the other respectively. These uses don't fit in the given question. The correct answer is C)with/ over.