Valentina is baking choco pies and choco cakes. each pie takes two times the number of chocolate bars as each cake. she plans to make 4 pies and 3 cakes. she wrote down the expression 4(2x) + 3(x) to model her baking plans. what does this entire expression represent? a. this expression represents the total number of chocolate bars used for all the pies. b.this expression represents the total number of chocolate bars used for all the cakes.  c. this expression represents the total number of cakes and pies being made.  d. this expression represents the total number of chocolate bars she will need for pies and cakes.