what is the simplified form of the following expression?
6c2 + 2.5d - d + 2c2 -3d
A4c2 - 1.5d
B6c2 + 0.5d
C8c2 -1.5d
D8c2 + 1.5d
6c2 + 2.5d - d + 2c2 -3d
A4c2 - 1.5d
B6c2 + 0.5d
C8c2 -1.5d
D8c2 + 1.5d