Match the following term with its definition 
I. Co-translational import     ______________________ 
II. Post-translational import ______________________ 
III. ER retention signal         ______________________ 
IV. Translocon                      ______________________ 


A. Pore in the ER membrane that binds SRP and SRPR to translocate the protein into ER
B. Signal sequence located on the C-terminus and keeps proteins within the ER 
C. Process of importing proteins into the ER as they're being translated 
D. importing proteins into the ER after they've been translated