HELPPP- PLSS ILL GIVE BRAIN THING

There are two kinds of endoplasmic reticulum (ER), smooth and rough. What is the difference between them?
A: Rough ER has ribosomes and smooth ER doesn't have ribosomes.
B: Smooth ER has ribosomes and rough ER doesn't have ribosomes.
C:Smooth ER makes proteins to be exported out of the cell and rough ER detoxifies chemicals.
D:There is no difference.