4.
A:
A competitive inhibition and substrate can blind simultaneously to the enzyme.
B:
The Vmax and Km (Michaels constant) for a reaction are unchanged in the presence of a competitive inhibitors
C:
The Vmax for a reaction remains unchanged in the presence of a competitive inhibitor.
D:
The Km for a reaction remans unchanged in the presence of a competitive inhibitor.
The answer is: C