Which of the Following Is the Main Difference Among the Active

Multiple Choice

Which of the following is the main difference among the active sites of all serine proteases?

A) the presence of serine residue at the active site
B) the size and charge of the pocket at the active site
C) the presence of histidine residue at the active site
D) the presence of aspartate at the active site
E) the hydrolysis of the peptide bond