The correct option is D Phospholipid synthesis
There are two basic types of ER (endoplasmic reticulum). Rough ER is called rough because it has ribosomes attached to its surface. It is involved in protein synthesis and secretion.
The smooth endoplasmic reticulum lacks ribosomes and is involved in the synthesis and storage of lipids.
Hence, phospholipid synthesis does not occur in a rough endoplasmic reticulum.