Edward wrote this expression to describe how much he paid for boxes of popcorn at the movie.

2 × c

which situation could be described by this expression?

a.
edward knows that each box costs $2. he knows that he is buying 2 boxes of popcorn.

b.
edward knows that each box of popcorn costs $2. he does not know much money he spent.

c.
edward knows he bought 2 boxes of popcorn. he does not know how much each box cost.

d.
edward knows that he bought 2 boxes of popcorn. he does not know the number of friends he will share the popcorn with.