Give the First Step of the Mechanism for Aldolase

Multiple Choice

Give the first step of the mechanism for aldolase.

A) Fructose-1,6,-diphosphate forms an imine with a lysine residue at the active site of the enzyme.
B) A tyrosine residue functions as a base catalyst to cleave the bond between C-3 and C-4.
C) The enamine intermediate rearranges to an imine.
D) Hydrolysis of the imine releases dihydroxyacetone phosphate.
E) A molecule of glyceraldehyde-3-phosphate is expelled.