The Rough ER and the Smooth ER Are Distinguished from Each

The rough ER and the smooth ER are distinguished from each other by

A) the presence or absence of membrane- bound ribosomes.
B) the presence or absence of membrane- bound ribosomes and the synthesis of lipids by the rough ER and the synthesis of proteins by the smooth ER.
C) the presence or absence of both DNA and membrane- bound ribosomes.
D) the presence of absence of DNA.
E) synthesis of lipids by the rough ER and synthesis of proteins by the smooth ER.