Fill in the blank with the most appropriate word.
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 A)in is correct as it indicates a judgement. The other options are wrong as on, for, with, and to indicate a surface, a purpose, inclusion, and a direction respectively. These uses don't fit in the given question. The correct answer is A)in.