The Conversion of Phosphoenolpyruvate and ADP to Pyruvate and ATP

Multiple Choice

The conversion of phosphoenolpyruvate and ADP to pyruvate and ATP occurs in two distinct steps, first the transfer of the phosphate from PEP to ADP, then the conversion of enolpyruvate to pyruvate. Which of the following describes the reversibility of this process?

A) both steps are freely reversible
B) step 1 is freely reversible, step 2 is irreversible
C) step 1 is irreversible, step 2 is freely reversible
D) both steps are irreversible
E) the reversibility of the reaction depends completely upon the concentrations of products and reactants