Which Is NOT Correct Concerning the Accepted Models That Describe

Which is NOT correct concerning the accepted models that describe cooperative binding?

A) In the sequential model, the binding of a ligand changes the conformation of the subunit to which it binds, in turn inducing a change in neighboring subunits.
B) All known allosteric proteins exhibit either the concerted or sequential model exclusive of the other.
C) Both models incorporate a low affinity T-state and a higher affinity R-state.
D) Both models explain the sigmoid-shaped binding curve.
E) In the concerted model, all molecules exist either in the T-state or the R-state.