Why Is the ER Ideal as a Port of Entry

Multiple Choice

Why is the ER ideal as a port of entry for secretory proteins?

A) The ER has a large surface area allowing for the attachment of many ribosomes.
B) The ER cisternae lumen favors unfolding and disassembly of proteins.
C) The RER can segregate secretory, lysosomal and cytoplasmic proteins from other newly made proteins, allowing their modification, and send them to their final destination.
D) The ER has a small surface area, allowing critical peptides to be concentrated into vesicles.