Actually, I think it is the one where the audience knows he will fail.
Dramatic Irony is when the audience knows something the reader does not.
"there is a last sweet and kind,
was never face so pleased my mind
I did but see her passing by
and yet I love her till I die
Foreshadowing means to give hints of the future. Like in "A Tale of two cities" by Charles Dickens, a man writes "Blood" on the wall, that word represents that there's probably a war coming.
Her parents are being thrifty, which means they're using money carefully by choosing a brand that even if it's not the most well known, it's good.