It might be stated that part 4 is included in order to provide a data-support information, that is to say, that this is not just an opinion but there have been researches on the matter, such as census and polls which might add validity to the statements. This is a way of showing that there is enough information to support the topic discussed.
C) Your father was in the suit and tie he always wore, his handsome, bespectacled face leaning toward someone in conversation.
