So, let's begin with diagram A. In diagram A, we have this beaker that contains pure water, and we also have the bag. Now, the bag is enclosed in a semipermeable membrane. So we have these tiny pores inside our bag. And these tiny pores allow the movement of very small molecules and ions, but prevent the movement of large molecules such as protein. So, inside the bag, we have this solution, where we have these protein molecules shown in purple, and these very tiny molecules shown in red.