The correct answer is for.
The preposition “for” is used to indicate the purpose or reason for something. In this case, the man is making up stories to account for his absence from work. This means that he is making up stories to explain why he was not at work.
The other prepositions do not make sense in this context. The preposition “to” is used to indicate a destination or goal. The preposition “of” is used to indicate possession or a part of something. The preposition “by” is used to indicate the means or method by which something is done.
Here are some examples of how the other prepositions could be used in a sentence:
- He went to the store to buy some milk.
- The car is made of metal.
- The painting was done by Picasso.