Which phrase from the paragraph best helps the reader understand the meaning of the underlined phrase?

I decided to have a sleepover and asked my closest friends. Then I decided to invite the new girl, Dawn, who had just moved in a few doors down. Little did I know that I would open a can of worms. I had no idea that my friend Jenn had already met Dawn and that the two girls totally disliked each other. If I had known I was going to create such a problem, I never would have had the sleepover.

A.
little did I know

B.
never would have had

C.
had no idea

D.
create such a problem