A Solution Containing Proteins of a Particular Type Is Exposed to the Same

Multiple Choice

A solution containing proteins of a particular type is exposed to the same concentrations of ligands X and Y,but the percent saturation of molecule X is greater than the percent saturation of molecule Y.Which is most likely to be a true statement?

A) The binding sites for ligand X are 100% saturated.
B) The binding sites for ligand X have greater specificity than the binding site for ligand Y. 
C) Ligand X must be a competitive inhibitor of ligand Y.
D) Both ligands must bind to the same binding site on the protein.
E) The protein has a higher affinity for ligand X than for ligand Y.