Which of the following Endoplasmic Reticulum is associated with Ribosomes?

The rough endoplasmic reticulum (RER) is studded with ribosomes on its outer surface, which gives it a rough appearance under a microscope. These ribosomes are responsible for protein synthesis, which occurs in the lumen of the RER. Proteins produced in the RER are often modified and folded before being transported to their final destination in the cell. In contrast, the smooth endoplasmic reticulum (SER) lacks ribosomes and is involved in lipid synthesis, calcium storage, and detoxification of drugs and poisons. The vacuolar endoplasmic reticulum is not a recognized type of endoplasmic reticulum.