Since Nina has to be in the middle, then there are four friends who can line up in different ways. We can write the equation as $$4\times3\times2\times1=24$$. 
Nina and four of her friends are lining up to take a picture. If Nina has to be in the middle, how many different ways can the five friends line up? 

A) $$6$$ 
B) $$12$$ 
C) $$24$$ 
D) $$120$$ 