Marissa bought x shirts that cost $19.99 each and y pairs of shorts that cost $14.99 each. The next day she went back to the store and bought 3 more shirts that cost $19.99 each and 4 more pairs of shorts that cost $14.99 each. Which expression represents the total amount Marissa spent?
A. X+3/19.99 + y+4/14.99
B. 3x/19.99 + 4y/14.99
C. 19.99(x+3) + 14.99(y+4)
D. (3x)19.99+(4y)14.99