Choose the option that fills the blank with the most suitable 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 B)by is correct as it means not later than. The other options are wrong as with, from, and since indicate inclusion, a source, and a duration with its starting point of time given respectively. These uses don't fit in the given question. The correct answer is B)by.