Correct Option: B

forecast (Noun) : a statement about what will happen in future
prognosis (Noun) : an opinion, based on medical experience, of the likely development of a disease or an illness; forecast; a judgement about how something is likely to develop in future
diagnosis (Noun) : the act of discovering or identifying the exact cause of an illness or a problem
preface (Noun) : an introduction to a book
identity (Noun) : who or what somebody or something is