Which expression is equivalent to 2.25 + 2.25x + 1 - 0.75x + 2x?
A6.75x
B8.25x
C3.5x + 3.25
D4.5 + 1 - 0.75x + 2x
A6.75x
B8.25x
C3.5x + 3.25
D4.5 + 1 - 0.75x + 2x