Figurative language refers to the use of words in ways that are not meant to be taken literally. It uses words in a way that deviates from their conventional use in order to convey a different meaning or heighten the effect of the speech. In this case, the phrase "to crush him like a fly" does not literally mean that Grendel wants to crush Unferth in the same way as a fly. The statement is not to be taken literally. Instead, it is intended to heighten the feeling of anger and frustration that Grendel feels towards Unferth.
Because when writing an introductory paragraph you suppose to have some biographic about the person and the year he/she was born. B is the best option there. I hope this help.
