You may be referring to the cytoplasm here. That is the "filling" within the cell. But if you are looking for specific transport of proteins, the ER folds proteins and then transport vesicles move them to the Golgi.
I think it is A but not 100% sure. Think of an enzyme like a key unlock the lock is the protein. And to activate getting inside your car or house you have to fit the key into the lock.
Drilling with pipe and mud
I dont know but if i did i would tell you
