Which of These Descriptions Applies to the Movement of Molecules

Multiple Choice

Which of these descriptions applies to the movement of molecules across the plasma membrane

A) If two similar molecules can both combine with the same carrier, the presence of one of these molecules increases the rate of entry of the other.
B) In simple diffusion, the rate of transport of a molecule is inversely proportional to the molecule's extracellular concentration.
C) When a carrier becomes saturated, the maximum rate of transport is reached.
D) Large molecules can cross it via nonselective, receptor-mediated endocytosis.