Cells that are lining digestive tube have microvilli. Some diseases may destroy them. What function of sells will be violated most of all?

Cells that are lining digestive tube have microvilli. Some diseases may destroy them. What function of sells will be violated most of all?

1.  Excretion


2.  Receptor


3.  Demarcation


4.  Division


5.  *Endocytosis